[quote= Jeb ...
" No pictures of my cam yet,
but it does appear to be similar to one shown in a previous post of a MotoTrans 250 scrambler cam, "
____ Wish you had included a link to whatever thread-post it was that you had found that shown in, as I (currently) don't recall ever seeing a cam profile pic.shot of any camshaft from a Mototrans 250-Scrambler model.
__ A Mototrans '250ROAD' model, of which it's appearance looks much the same as a Ducati-Scrambler,, actually employs a 'Violet/Monza-cam.model', which is considered as Ducati's mildest cam.model (with it's relatively-modest [20bt - 70ab / 50bb - 30at] valve-timing).
" so I can assume it is a fairly wild cam as that one was thought to be. "
____ Generally, while Scrambler-cam.models are-not the mildest, their lobe-profile is-not considered as the 'wild' type !
__ Most-all of us here who've ever taken note of the cam-lobe shapes of the various Ducati cam.models, can easily recognize the obvious-difference which the shape of the lobe-profiles of wild-cams distinctly exhibit compared to the mild-type (within the duration-area of 'overlap').
" My cam does have a split / drift pin in the drive end allready. "
____ Then most certainly your cam likely suffered from one or both common-problems which I've already previously mentioned.
" it may be best for me to do a trial assembly of the engine, and set up to take measurements of the cam timing periods. "
____ I'm fairly sure that relatively extensive setup-work would be less accurate and more difficult for you to get accomplished than doing the like of setting-up your camshaft (with attached degree-wheel) within a lathe-chuck (or drill-press) and checking it's lobe-variances with a stationary dial-indicator.
If you have any access to the like, I'll then offer explanation-help of how to get things set up (if you run-into any trouble doing-so on your-own).
" I realise that it is not likely to be perfectly accurate, "
____ Should be accurate enough, providing that you get your readings taken from the unworn edge of the cam-lobes.
" it will give me a better idea or which cam it is, by comparing with the figures previously given for the cams fitted to MotoTrans engines. "
____ Perhaps Jon (or one of our other members outside of the U.S.) can tell us how likely it is for stock Mototrans-camshafts to include any kind of oil-blockage at the threaded-end of the shaft (as you've found). _ As that difference may help indicate whether your cam.model is actually an original for your 250-Mototrans.
__ So what's your specific hope in learning which cam.model you have ?
Are you still considering whether it's more important for you to keep your engine's stock valve-timing just as 'original', or rather merely just wishing to get a decent grasp on exactly how much milder you prefer your engine's power-delivery to behave.
__ I'd preferably recommend the employment of milder cams within the less 'over-square' engines as your 69x66mm-B&S 250, since it makes better sense to compile the low-end advantage (which the added 4.1mm crank-leverage [of the 8.2mm longer-stroke] is more-inclined to provide for your 250 [vs. the higher-revving 74x57.8mm 250-engine]).
" I will take pictures of the engine etc, and post "
____ Especially looking forward to the pic of your camshaft's ex.lobe-profile* !
(* Which is best squarely-done with your camera's lens perfectly aligned with the hole through the c.shaft, [which can be made certain by having the camera see a light shown through that hole] !)
Hopeful-Cheers,
-Bob
Mototrans 250 help / advice wanted.
Moderator: ajleone
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DewCatTea-Bob
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Re: Mototrans 250 help / advice wanted.
PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob
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Jon Pegler
- Posts: 467
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Re: Mototrans 250 help / advice wanted.
Most of the late (post 1970 ) Mototrans camshafts seem to have a roll pin pressed into the end of the camshaft to increase the oil flow to the cam lobes and rockers, so Jebs cam may well have come like that as standard.
I'm not sure the 250 Road ever came with the violet cam Bob suggests.
The widecase Road came with the white cam, which is still a fairly mild profile. part no.0601.29.010
The 5-speed narrowcase Road came with the wilder cam I posted figures for earlier.
However, the Spanish parts book for that model lists the cam as part no. 0603.29.010 - the grey cam as fitted to the Mach 1 etc..
This cannot be exactly the same cam as the narrowcase Road uses the shorter cam due to the narrower headbolt spacing used by the late Spanish narrowcase machines.
Quite what the explanation for this is I don't know.
Jon
I'm not sure the 250 Road ever came with the violet cam Bob suggests.
The widecase Road came with the white cam, which is still a fairly mild profile. part no.0601.29.010
The 5-speed narrowcase Road came with the wilder cam I posted figures for earlier.
However, the Spanish parts book for that model lists the cam as part no. 0603.29.010 - the grey cam as fitted to the Mach 1 etc..
This cannot be exactly the same cam as the narrowcase Road uses the shorter cam due to the narrower headbolt spacing used by the late Spanish narrowcase machines.
Quite what the explanation for this is I don't know.
Jon
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DewCatTea-Bob
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Re: Mototrans 250 help / advice wanted.
[quote= Jon Pegler ...
" I'm not sure the 250 Road ever came with the violet cam Bob suggests. "
____ Back in the early-70s, I had always assumed that the '250 ROAD' model came with the same cam.model as most-all other w-c.250-Scrambler models (which would be a 'White'/#0601.29.010 camshaft-type),, and when I finally removed the camshaft from one of those Mototrans-made models (by 1978), it did indeed appear to be same as a w-c.250-Scr.cam as had been expected, (and certainly not as a n-c.Monza/Violet cam.model) !
However I'm still pretty-sure that I had once seen the camshaft-spec.figures within a trustworthy listing that stated the 250-ROAD's valve-timing as rather being exactly the same as that of the Violet-cam,, and that revelation was such a surprise to me at the time, that I've never since forgot about that ! _ And-also when I recently looked-over a friend's DUCATI-book by Mick Walker (for the purpose of looking-up the valve-timing of n-c.250Mototrans-models), I there too found those same Violet-type timing-figures confirmed ! _ So naturally it all seemed reasonably trustworthy to go-ahead & post those figures as if fact.
__ But now thankfully Jon has brought that into question, thus motivating me to bother with looking-up my original 250-ROAD owner's-manual to confirm whether that's where I had correctly assumed I had once-before seen the Violet timing-figures listed within.
BUT instead I found valve-timing figures (within that owner's-manual) which are consistent with the White cam.model-type !
So it seems that the Mick Walker listing is wrong (in that particular regard, I guess).
" The widecase Road came with the white cam, which is still a fairly mild profile. "
____ A mild-profile indeed, but it's v.timing is somewhat on the wild-side...
with timing-figures of: 30bt - 84ab / 63bb - 38at !
Temp.NOTE: Sorry for the extended delay completing this post ! ... After I began this posting, I started to experience one of my rare RA.attacks which got so intense that I became too ill to continue-on any further than this point with completing this post !
When I finally near-fully recover back to normal, I'll then endeavor to finally complete this post.
The 5-speed narrowcase Road came with the wilder cam I posted figures for earlier.
However, the Spanish parts book for that model lists the cam as part no. 0603.29.010 - the grey cam as fitted to the Mach 1 etc.. "
____ If that parts-book is actually correct, then that would be the third camshaft that falls-under the Gray color-code & 0603.29.010 part.number ! ...
(Besides the original Mach-I cam.model,, the w-c.Mark-3 cam.model [with it's unique timing-specs of: 63bt - 71ab / 71bb - 51at], also unfortunately received the same color-code & part-number designations !)
" This cannot be exactly the same cam as the narrowcase Road uses the shorter cam due to the narrower headbolt spacing used by the late Spanish narrowcase machines. "
____ I've come to reasonably understand that the 4-speed 69x66-B&S 250Mototrans-motors employed the 175/200-type square bolt-pattern cyl.heads which can only contain the shorter-length camshafts,, so therefore in that case, the 0603 part-number indeed could-not possibly apply ! _ So it seems that what you've looked-up in your parts-book, must be in error.
" Quite what the explanation for this is I don't know. "
____ My possible explanation/guess is that later/5-speed 'n-c.200-C' type Mototrans 250-motors rather employed std.250-type cyl.heads which were naturally capable of containing the longer-type camshafts.
So it would be worth checking to see whether your Mototrans parts-book possibly actually provides separate distinct part-numbers for the respective cyl.heads of the 4-speed & 5-speed 250-motors, (in which case the old-style cyl.head's part-number should begin with 040 . and the std.250-head ought begin with 060 .).
This really ought-to be found to be the actual circumstance, since Nigel has previously posted evidence* to support this likely correct deduction, (* as found by this link - viewtopic.php?f=3&t=1796&p=13196#p13190 .
Concerning Nigel's related post-comment (in reference-to the 200-C cyl.base-gasket), he stated:
__ Please let us know if this likely explanation solves the mystery.
Hopeful-Cheers,
-Bob
" I'm not sure the 250 Road ever came with the violet cam Bob suggests. "
____ Back in the early-70s, I had always assumed that the '250 ROAD' model came with the same cam.model as most-all other w-c.250-Scrambler models (which would be a 'White'/#0601.29.010 camshaft-type),, and when I finally removed the camshaft from one of those Mototrans-made models (by 1978), it did indeed appear to be same as a w-c.250-Scr.cam as had been expected, (and certainly not as a n-c.Monza/Violet cam.model) !
However I'm still pretty-sure that I had once seen the camshaft-spec.figures within a trustworthy listing that stated the 250-ROAD's valve-timing as rather being exactly the same as that of the Violet-cam,, and that revelation was such a surprise to me at the time, that I've never since forgot about that ! _ And-also when I recently looked-over a friend's DUCATI-book by Mick Walker (for the purpose of looking-up the valve-timing of n-c.250Mototrans-models), I there too found those same Violet-type timing-figures confirmed ! _ So naturally it all seemed reasonably trustworthy to go-ahead & post those figures as if fact.
__ But now thankfully Jon has brought that into question, thus motivating me to bother with looking-up my original 250-ROAD owner's-manual to confirm whether that's where I had correctly assumed I had once-before seen the Violet timing-figures listed within.
BUT instead I found valve-timing figures (within that owner's-manual) which are consistent with the White cam.model-type !
So it seems that the Mick Walker listing is wrong (in that particular regard, I guess).
" The widecase Road came with the white cam, which is still a fairly mild profile. "
____ A mild-profile indeed, but it's v.timing is somewhat on the wild-side...
with timing-figures of: 30bt - 84ab / 63bb - 38at !
Temp.NOTE: Sorry for the extended delay completing this post ! ... After I began this posting, I started to experience one of my rare RA.attacks which got so intense that I became too ill to continue-on any further than this point with completing this post !
When I finally near-fully recover back to normal, I'll then endeavor to finally complete this post.
The 5-speed narrowcase Road came with the wilder cam I posted figures for earlier.
However, the Spanish parts book for that model lists the cam as part no. 0603.29.010 - the grey cam as fitted to the Mach 1 etc.. "
____ If that parts-book is actually correct, then that would be the third camshaft that falls-under the Gray color-code & 0603.29.010 part.number ! ...
(Besides the original Mach-I cam.model,, the w-c.Mark-3 cam.model [with it's unique timing-specs of: 63bt - 71ab / 71bb - 51at], also unfortunately received the same color-code & part-number designations !)
" This cannot be exactly the same cam as the narrowcase Road uses the shorter cam due to the narrower headbolt spacing used by the late Spanish narrowcase machines. "
____ I've come to reasonably understand that the 4-speed 69x66-B&S 250Mototrans-motors employed the 175/200-type square bolt-pattern cyl.heads which can only contain the shorter-length camshafts,, so therefore in that case, the 0603 part-number indeed could-not possibly apply ! _ So it seems that what you've looked-up in your parts-book, must be in error.
" Quite what the explanation for this is I don't know. "
____ My possible explanation/guess is that later/5-speed 'n-c.200-C' type Mototrans 250-motors rather employed std.250-type cyl.heads which were naturally capable of containing the longer-type camshafts.
So it would be worth checking to see whether your Mototrans parts-book possibly actually provides separate distinct part-numbers for the respective cyl.heads of the 4-speed & 5-speed 250-motors, (in which case the old-style cyl.head's part-number should begin with 040 . and the std.250-head ought begin with 060 .).
This really ought-to be found to be the actual circumstance, since Nigel has previously posted evidence* to support this likely correct deduction, (* as found by this link - viewtopic.php?f=3&t=1796&p=13196#p13190 .
Concerning Nigel's related post-comment (in reference-to the 200-C cyl.base-gasket), he stated:
So sensibly, it seems fittingly reasonable that the 5-speed 69mm.bore 250-motors would also rather employ the std.250-type cyl.head (with it's widened-out bolt-pattern [for including containment of the longer-type camshafts]) !- last incarnation which is effectively as a 250 gasket but with a smaller hole for the cylinder. This engine was effectively a 4 speed 250 with cases and cylinder machined to suit the smaller liner and piston. The head was machined accordingly to suit the 200 hemi chamber with no squish but otherwise was as a 250 casting with the "rectangular" bolt pitch.
__ Please let us know if this likely explanation solves the mystery.
Hopeful-Cheers,
-Bob
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PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob
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Jeb
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Re: Mototrans 250 help / advice wanted.
Sorry again for my delay in replying .
I do not know how to, or if I can link to another discussion, but the cam picture I was refering to is in the discussion from NewKidOnTheBlock on May 18 2014, headed Tuning a Mototrans 250. I thought this was from a Scrambler model when I mentioned it in my last post, but having now re read the discussion, I see it is not. But. it does look very similar to mine pictured below. The cam of NKOTB was from a NC 4 speed, mine is from a NC 5 speed, and my cyl head does also have square bolt pattern.
I do not know how to, or if I can link to another discussion, but the cam picture I was refering to is in the discussion from NewKidOnTheBlock on May 18 2014, headed Tuning a Mototrans 250. I thought this was from a Scrambler model when I mentioned it in my last post, but having now re read the discussion, I see it is not. But. it does look very similar to mine pictured below. The cam of NKOTB was from a NC 4 speed, mine is from a NC 5 speed, and my cyl head does also have square bolt pattern.
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Jon Pegler
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Re: Mototrans 250 help / advice wanted.
The cam I listed as used on the 5-speed narrowcase Mototrans models was part no. 0603.29.010 which would appear to be the longer camshaft used on the later Italian models.
This number was quoted as the correct cam in two different narrowcase Mototrans parts books.
The cam fitted into the narrowcase 5-speed mototrans machines is the shorter cam, more like the Italian 175s and Elites.
All the narrowcase 5-speed Mototrans machines are listed as using this cam, together with the narrow head bolt spacing, whether they employ the 'square' cylinder base gasket or the more 'barrel' shaped base gasket.
The first Spanish 250s to use the longer camshaft was the 250 Road widecase followed in 1978 by the Strada, using the white camshaft and the grey camshaft respectively ( 0601.29.010 and 0603.29.010 ). As quoted in two different widecase Mototrans parts books.
Just to confuse matters,the last Spanish Elites were 5-speed models with the barrel shaped base gasket, but I have seen evidence of a 5-speed model with the square base gasket, just at the change over period from 4-speed to 5-speed, at engine no. 829xx.
It's always fun with Mototrans Ducatis.
Jon
This number was quoted as the correct cam in two different narrowcase Mototrans parts books.
The cam fitted into the narrowcase 5-speed mototrans machines is the shorter cam, more like the Italian 175s and Elites.
All the narrowcase 5-speed Mototrans machines are listed as using this cam, together with the narrow head bolt spacing, whether they employ the 'square' cylinder base gasket or the more 'barrel' shaped base gasket.
The first Spanish 250s to use the longer camshaft was the 250 Road widecase followed in 1978 by the Strada, using the white camshaft and the grey camshaft respectively ( 0601.29.010 and 0603.29.010 ). As quoted in two different widecase Mototrans parts books.
Just to confuse matters,the last Spanish Elites were 5-speed models with the barrel shaped base gasket, but I have seen evidence of a 5-speed model with the square base gasket, just at the change over period from 4-speed to 5-speed, at engine no. 829xx.
It's always fun with Mototrans Ducatis.
Jon
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DewCatTea-Bob
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Re: Mototrans 250 help / advice wanted.
[quote= Jon Pegler ...
" The cam I listed as used on the 5-speed narrowcase Mototrans models was part no. 0603.29.010 which would appear to be the longer camshaft used on the later Italian models.
This number was quoted as the correct cam in two different narrowcase Mototrans parts books.
The cam fitted into the narrowcase 5-speed mototrans machines is the shorter cam, more like the Italian 175s and Elites. "
____ Of-course your posted-wording which I've quoted in bold-print, contradicts what you've stated you found within your copies of Mototrans parts-books. _ However even-so, I can still accept that those two somewhat oppositional statements are in fact, both true.
So this would seem to indicate that if a n-c.250-Mototrans owner had ever ordered a new replacement-0603.29.010-camshaft from Italy, he then could've found it to be too long to fit & work within his square bolt-pattern cyl.head-type.
" All the narrowcase 5-speed Mototrans machines are listed as using this cam, together with the narrow head bolt spacing, whether they employ the 'square' cylinder base gasket or the more 'barrel' shaped base gasket. "
____ I had offered a possible and seemingly logical explanation for how your Mototrans parts-books could be actually correct (concerning the indication that the longer-type camshaft is stock also for n-c.250-Mototrans motors with the square bolt-pattern), but I now find myself informed that all n-c.250-Mototrans motors apparently didn't logically also follow the Italian 200-motor updating train-of-events which had all the newest (over 160cc) n-c.engine-versions adopting the widened bolt-pattern of all the Italian 250-motors. _ So I must now accept that my previously offered explanation-theory is-not the actual correct answer for proper detail-consolidation of the presented seemingly-contradictory evidence-details.
__ So my next offered reasoning for possible consolidation of the seemingly-contradictory camshaft details, is rather having to do with the adaptation of the newer/longer-version camshaft-type within the older-type cyl.head with the square bolt-pattern...
__ While it's quite possible to install the slightly-shorter/175-type camshaft-version within the newer/widened 250-cyl.head-type camshaft-tunnel/cavity,, conversely, the newer/longer-type camshaft won't allow a (std.Italian-type) '250cc' camshaft-support/cover to fully install into it's normal/completely-seated position within an older/175-type cyl.head (which hasn't had it's tunnel-cavity lengthened) !
So to compensate for this misfitting, the 'Made in Spain'/Mototrans camshaft-support/left-side,head-cover must allow for a slightly deeper-set positioning of the camshaft's support-bearing (further within that left-side bearing-support/head-cover).
__ So-thus in order for those Mototrans parts-books to be correlatingly-correct (that the n-c.250-Mototrans engine-heads actually do indeed accept the longer-type camshaft-version), then their given associated part-number for the longer-camshaft's bearing-support/head-cover must be different than that intended for the Italian-type 250-cyl.heads (which include an added section to the left-side end of the camshaft-tunnel/cavity length) !
So-then whatever parts-book model-pages indicate the long-type 0603.29.010-camshaft (for the Mototrans n-c.250-cyl.head), the corresponding model-pages showing the associated cyl.head-parts SHOULD list a unique part-number for the corresponding/adapted bearing-support/cover !
" The first Spanish 250s to use the longer camshaft was the 250 Road widecase followed in 1978 by the Strada, using the white camshaft and the grey camshaft respectively ( 0601.29.010 and 0603.29.010 ). As quoted in two different widecase Mototrans parts books. "
____ So are you meaning to indicate that the "narrowcase Mototrans" parts-books are simply wrong (about indicating the part-number of a longer-type camshaft being suited for a Mototrans n-c.250-cyl.head) ?
__ To the most logical-minded of us,, it would seem fairly suitable that the longer-camshafts would've only been employed just within the widecase-motors, (just as it seems that Mototrans had reasoned).
I'm at a loss for a good reasonable explanation for why Ducati had ever bothered to lengthen the original camshaft-length in the first-place, as that change thus-then required that the camshaft-tunnel/cavity had to be accordingly lengthened also as-well ! _ And the widening of the cyl.head bolt-pattern should-not've caused any associated need (that I can think of) for either the camshaft-length or it's head-cavity's length to require any resulting increase to go-with. _ So it seems there was no good reason for Ducati to've ever bothered with the redesigning of the camshaft's original/short-length !
" the last Spanish Elites were 5-speed models with the barrel shaped base gasket, "
____ So then did those n-c.Mototrans-models finally include the longer camshaft-version ?
" but I have seen evidence of a 5-speed model with the square base gasket, just at the change over period from 4-speed to 5-speed, at engine no. 829xx.
It's always fun with Mototrans Ducatis. "
____ I've always regretted that all Mototrans Duke-models weren't also imported into the U.S., as I've felt left-out of the loop concerning all their additional model-variances ! _ However I'm now coming to realize that even the likes of myself would probably be overwhelmed with trying to keep all the additional varied details all clearly straight within mind ! _ So I'm thinking maybe I wouldn't be as knowledgeable about the Italian-versions in the first-place, if I had also had so much extra Mototrans-version details to concurrently learn as well.
Enlightened-Cheers,
DCT-Bob
" The cam I listed as used on the 5-speed narrowcase Mototrans models was part no. 0603.29.010 which would appear to be the longer camshaft used on the later Italian models.
This number was quoted as the correct cam in two different narrowcase Mototrans parts books.
The cam fitted into the narrowcase 5-speed mototrans machines is the shorter cam, more like the Italian 175s and Elites. "
____ Of-course your posted-wording which I've quoted in bold-print, contradicts what you've stated you found within your copies of Mototrans parts-books. _ However even-so, I can still accept that those two somewhat oppositional statements are in fact, both true.
So this would seem to indicate that if a n-c.250-Mototrans owner had ever ordered a new replacement-0603.29.010-camshaft from Italy, he then could've found it to be too long to fit & work within his square bolt-pattern cyl.head-type.
" All the narrowcase 5-speed Mototrans machines are listed as using this cam, together with the narrow head bolt spacing, whether they employ the 'square' cylinder base gasket or the more 'barrel' shaped base gasket. "
____ I had offered a possible and seemingly logical explanation for how your Mototrans parts-books could be actually correct (concerning the indication that the longer-type camshaft is stock also for n-c.250-Mototrans motors with the square bolt-pattern), but I now find myself informed that all n-c.250-Mototrans motors apparently didn't logically also follow the Italian 200-motor updating train-of-events which had all the newest (over 160cc) n-c.engine-versions adopting the widened bolt-pattern of all the Italian 250-motors. _ So I must now accept that my previously offered explanation-theory is-not the actual correct answer for proper detail-consolidation of the presented seemingly-contradictory evidence-details.
__ So my next offered reasoning for possible consolidation of the seemingly-contradictory camshaft details, is rather having to do with the adaptation of the newer/longer-version camshaft-type within the older-type cyl.head with the square bolt-pattern...
__ While it's quite possible to install the slightly-shorter/175-type camshaft-version within the newer/widened 250-cyl.head-type camshaft-tunnel/cavity,, conversely, the newer/longer-type camshaft won't allow a (std.Italian-type) '250cc' camshaft-support/cover to fully install into it's normal/completely-seated position within an older/175-type cyl.head (which hasn't had it's tunnel-cavity lengthened) !
So to compensate for this misfitting, the 'Made in Spain'/Mototrans camshaft-support/left-side,head-cover must allow for a slightly deeper-set positioning of the camshaft's support-bearing (further within that left-side bearing-support/head-cover).
__ So-thus in order for those Mototrans parts-books to be correlatingly-correct (that the n-c.250-Mototrans engine-heads actually do indeed accept the longer-type camshaft-version), then their given associated part-number for the longer-camshaft's bearing-support/head-cover must be different than that intended for the Italian-type 250-cyl.heads (which include an added section to the left-side end of the camshaft-tunnel/cavity length) !
So-then whatever parts-book model-pages indicate the long-type 0603.29.010-camshaft (for the Mototrans n-c.250-cyl.head), the corresponding model-pages showing the associated cyl.head-parts SHOULD list a unique part-number for the corresponding/adapted bearing-support/cover !
" The first Spanish 250s to use the longer camshaft was the 250 Road widecase followed in 1978 by the Strada, using the white camshaft and the grey camshaft respectively ( 0601.29.010 and 0603.29.010 ). As quoted in two different widecase Mototrans parts books. "
____ So are you meaning to indicate that the "narrowcase Mototrans" parts-books are simply wrong (about indicating the part-number of a longer-type camshaft being suited for a Mototrans n-c.250-cyl.head) ?
__ To the most logical-minded of us,, it would seem fairly suitable that the longer-camshafts would've only been employed just within the widecase-motors, (just as it seems that Mototrans had reasoned).
I'm at a loss for a good reasonable explanation for why Ducati had ever bothered to lengthen the original camshaft-length in the first-place, as that change thus-then required that the camshaft-tunnel/cavity had to be accordingly lengthened also as-well ! _ And the widening of the cyl.head bolt-pattern should-not've caused any associated need (that I can think of) for either the camshaft-length or it's head-cavity's length to require any resulting increase to go-with. _ So it seems there was no good reason for Ducati to've ever bothered with the redesigning of the camshaft's original/short-length !
" the last Spanish Elites were 5-speed models with the barrel shaped base gasket, "
____ So then did those n-c.Mototrans-models finally include the longer camshaft-version ?
" but I have seen evidence of a 5-speed model with the square base gasket, just at the change over period from 4-speed to 5-speed, at engine no. 829xx.
It's always fun with Mototrans Ducatis. "
____ I've always regretted that all Mototrans Duke-models weren't also imported into the U.S., as I've felt left-out of the loop concerning all their additional model-variances ! _ However I'm now coming to realize that even the likes of myself would probably be overwhelmed with trying to keep all the additional varied details all clearly straight within mind ! _ So I'm thinking maybe I wouldn't be as knowledgeable about the Italian-versions in the first-place, if I had also had so much extra Mototrans-version details to concurrently learn as well.
Enlightened-Cheers,
DCT-Bob
PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob
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DewCatTea-Bob
- Posts: 2897
- Joined: Sun Nov 01, 2009 10:53 am
- Location: Near SE side of Lake Michigan
Re: Mototrans 250 help / advice wanted.
[quote= Jeb ...
" I do not know how to, or if I can link to another discussion, but the cam picture I was refering to is in the discussion from NewKidOnTheBlock on May 18 2014, headed Tuning a Mototrans 250. "
____ Okay, thanks for letting me know what cam-picture it was that you had found.
Here's a link to that post... viewtopic.php?f=3&t=1766&start=20#p12963
" it does look very similar to mine pictured below. "
____ I've included a combo-pic allowing direct comparison of his cam next to yours.
While neither pic.shot has been taken from the desired perfect-angle squarely at a right-angle to the shaft-length, your pic.shot's view-angle happens to seem thoughtfully off-angle in a preferable direction which allows better viewing of the entire intake-lobe, (although your camera-lens seems well focused only upon the ex.lobe, with most other surfaces appearing rather blurry due-to having the camshaft posed too closely-near your camera).
__ I don't recognize your cam.model, so it must indeed be a Mototrans-version.
While it's lobe-profile doesn't exhibit the typical classic-Ducati wild-cam eccentric-profile,, it's lobe-duration appears somewhat notably greater than the other given example, and certainly even more-so than that of a Monza/Scrambler-type cam !
So while your cam doesn't seem to exploit wild 'overlap', it probably does have rather wild 'duration',, which tends to lead me to deduct that if yours is indeed the wilder cam that Jon has mentioned, then the other example must likely be the milder DeLuxe-version.
__ Have you gathered any other clues that indicate your 250-Mototrans Duke-model might be a 24-Horas model ?
Temp.NOTE: Sorry for the 20-hour delay in getting this post completely finished !
This time the responsible cause of the delay-issue was due-to extended loss of my connection to the internet, (which often occurs but not for such an excessive length of time).
" mine is from a NC 5 speed, and my cyl head does also have square bolt pattern. "
____ That confirms your 250-Duke is indeed a Mototrans-model,, however to help confirm whether your 250-cyl.head can accept the longer-type camshaft, could you post a pic.shot showing a nearly overhead-view of it's camshaft-tunnel opening, (preferably with it's bearing-support removed) ? _ And-also a picture showing the bearing-containment/inside-end of the support/cover itself.
Then hopefully we'll be able to determine whether you could possibly opt to rather-simply install either of the camshaft-length versions.
Hopeful-Cheers,
-Bob
" I do not know how to, or if I can link to another discussion, but the cam picture I was refering to is in the discussion from NewKidOnTheBlock on May 18 2014, headed Tuning a Mototrans 250. "
____ Okay, thanks for letting me know what cam-picture it was that you had found.
Here's a link to that post... viewtopic.php?f=3&t=1766&start=20#p12963
" it does look very similar to mine pictured below. "
____ I've included a combo-pic allowing direct comparison of his cam next to yours.
While neither pic.shot has been taken from the desired perfect-angle squarely at a right-angle to the shaft-length, your pic.shot's view-angle happens to seem thoughtfully off-angle in a preferable direction which allows better viewing of the entire intake-lobe, (although your camera-lens seems well focused only upon the ex.lobe, with most other surfaces appearing rather blurry due-to having the camshaft posed too closely-near your camera).
__ I don't recognize your cam.model, so it must indeed be a Mototrans-version.
While it's lobe-profile doesn't exhibit the typical classic-Ducati wild-cam eccentric-profile,, it's lobe-duration appears somewhat notably greater than the other given example, and certainly even more-so than that of a Monza/Scrambler-type cam !
So while your cam doesn't seem to exploit wild 'overlap', it probably does have rather wild 'duration',, which tends to lead me to deduct that if yours is indeed the wilder cam that Jon has mentioned, then the other example must likely be the milder DeLuxe-version.
__ Have you gathered any other clues that indicate your 250-Mototrans Duke-model might be a 24-Horas model ?
Temp.NOTE: Sorry for the 20-hour delay in getting this post completely finished !
This time the responsible cause of the delay-issue was due-to extended loss of my connection to the internet, (which often occurs but not for such an excessive length of time).
" mine is from a NC 5 speed, and my cyl head does also have square bolt pattern. "
____ That confirms your 250-Duke is indeed a Mototrans-model,, however to help confirm whether your 250-cyl.head can accept the longer-type camshaft, could you post a pic.shot showing a nearly overhead-view of it's camshaft-tunnel opening, (preferably with it's bearing-support removed) ? _ And-also a picture showing the bearing-containment/inside-end of the support/cover itself.
Then hopefully we'll be able to determine whether you could possibly opt to rather-simply install either of the camshaft-length versions.
Hopeful-Cheers,
-Bob
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PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob
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