New here: questions installing entire kick start

[adammccarty]

[quote= adammccarty ...
" how do I get the gear off? "

____ Once the retaining-nut has been removed, that gear usually just pulls-off by hand,, but it looks-like a std.claw-puller would pull it off alright.


Hopeful-Cheers,
-Bob

Tried that, only place to grab to is shims behind and worried about damaging them. Thing is on there no idea how it got so stuck

[adammccarty]

Well, assume this is why it was so difficult to remove. How screwed am I? Anyone had this happen to a key before? Recommendations on how to remedy?

[themoudie]

Aye Adam,

That is a split the cases, crankshaft out and down to a good machine shop job. Have to split the crank and then metal spray the crank and re-machine the shaft and keyway. This will not be a "cheap" job and whilst you are at it you should have the big-end and the centrifugal oil filter cleaned and renewed, where necessary, afore rebuilding.

I had the nut holding the crankshaft gear and rotor onto its taper come loose, resulting in my taper and the shaft and keyway looking like yours (chewed!). A competent engineering machine shop was the only answer.

My apologies for being such a gloom munger.

My regards, Bill.

[DewCatTea-Bob]

[quote= adammccarty ...
" Well, assume this is why it was so difficult to remove. How screwed am I? "

____ Now that Bill has placed his post, I'm become inspired to wonder just exactly what you were really meaning to be referring to specifically !?



" Anyone had this happen to a key before? Recommendations on how to remedy? "

____ Yes, I've seen such wreckage of the key before, pretty-much just-like you've got pictured.
I've found such similar sheared-off keys in 350/450-engines where the crankshaft-nut wasn't remaining torqued-down as tight as it should be, and-thus the key-itself was left to carry the load pretty-much all on it's own, (and IT alone, can't take that abuse !).
__ I had before meant to download your picture, then enhance it (as I've now posted) so I could then have a better look at your key's particular situation,, but before actually acquiring a sample of your pic into my PC, I lost my internet-connection and-then later forgot to get back to the job, (until Bill's posting brought your post back to my attention again).
So now everyone should be able to have a close look and see the outline of the key within it's slot in the shaft.
__ To extract the remainder of the key,, try placing the point of a punch near one end of it, and clobber it so as to rock the key within it's slot and-thus cause it's opposite-end to-be forced upward & out far enough to grab it with vice-grips, and then pull it out of the shaft's slot.
Then all you should need, is a new key.
__ I've had to do that procedure a few times, and it has always worked-out well enough for me. _ But if you have any trouble getting the key to move, then try some heat & cold on the area nearest the key.


Hopeful-Cheers,
-Bob

[DewCatTea-Bob]

[quote= themoudie ...
" I had the nut holding the crankshaft gear and rotor onto its taper come loose, resulting in my taper
looking like yours (chewed!). A competent engineering machine shop was the only answer. "

____ Of-course there's certainly nothing wrong with preferring to have such machine-work be in normal perfect & pretty condition ! _ However (in this case), I'd say that such desire is fairly much the same kind of predicament as having to choose how to deal with the situation of repainting fenders to a new color...
It'd be sort-of desirable to also bother-with having the underside of the fenders nicely refinished as well,
but is that out-of-sight area REALLY necessary to have redressed for functional-purposes ?
Well probably not, if ya don't wish to forgo the added expense & associated extra procedures.
And the damage to the shaft-taper is pretty-much the same kind of situation, since actual FUNCTIONALITY is-not really adversely affected (beyond workability). ...
__ I've encountered crankshaft-tapers which were FAR,far,far-MORE chewed-up/torn-up/dug-up/scraped-up (and generally just plain SCREWED-up), than that relatively minor wear which can be seen on the taper of THIS posted crankshaft !!
And (in most cases), all that ever got done to address the matter, was to simply clean-off* the taper (as well as that of the rotor's),, then carefully locate the flywheel-rotor back in place, and torque-down the rotor-taper against the shaft-taper just a few extra ft/lbs (than factory-recommended). _ And that's all that's needed to be just as functionally secure as a nice & pretty factory-finished taper-dressing.
(* Not to be confused with 'refinishing'.)
And while the nicer appearing stock crankshaft/flywheel-rotor taper-fittings are known to possibly break-loose with their original factory-finished taper-surfaces,
I've never seen any badly-worn/screwed-up tapers break-loose again (after being simply reinstalled while left in their 'as-is' screwed-up state of condition). - (So it sort-of seems that screwed-up taper-surfaces might possibly get a better grip of one-another.)
__ So bottom-line is,, unless it's important to ya for everything to look nice & proper (even when ya can't really see it after installation), then there's really no need to-be concerned with the whole involved matter (related with the 'refinishing' of the tappers' surface-dressing).
So I'd suggest letting such perfection-type work wait to get fully addressed sometime in the future, when there then might be some other reason to rework the crankshaft as well.



" My apologies for being such a gloom munger. "

____ Well that may've given ME the opportunity to cancel the likely gloom AND rather raise the mood in the opposite direction,
(whereas before, my info would've been taken merely neutrally).


Hopeful-Cheers,
DCT-Bob

[StewartD]

Hi Adam,

I don't think the damage looks that bad, I agree with Bob's answer. I had a 450 shear its key and had to fix it on the side of the road. We went into a farmer's property and hacksawed a piece of steel to the woodruff key profile and then used the bench grinder to get the thickness right. The taper for the flywheel was a bit damaged, but I torqued up the nut using a bar about 2 foot long and that repair lasted for years after without a problem. I may have eventually put a new key in; I know the roadside repair didn't fail.

I also think using lock tab washers is a bit of a poor option. These washers are of low grade steel so that they are weak enough to bend up. There are a couple of reasons that they will give trouble.

First: The locking tab may not stop the nut rotating a very small amount. The tab will then stop the nut rotating, but the rot has now set in. A slightly rotated nut will result in slightly less force in the contacting faces, small amounts of movement will then fret away at the low grade tab washer creating further reduction in the force that holds that taper joint together.

Second: Because the washer is a low grade steel, it may crush slightly after the engine goes through a heating cooling cycle. It is a weak link in transmitting the force of the nut to the taper joint. Once it has crushed slightly then the force is reduced leading to slight movements, fretting wear and failure.

I always used hardened steel washers on my 450, a drop of locktite and the long socket bar. If the threads are o.k. you will not strip them. I also ditched the lock tab washers on the TZ Yamahas I raced for many years, used about 3 foot of socket bar and really heaved on it

Cheers.

Stewart D

[themoudie]

Good evening Adam, Bob and Stewart,

Delighted to read that 'patina' and 're-cycling', along with 'bush engineering' are still alive and well on this site.

Having lived with my 450 since '76 and carried out numerous 'alternative' repairs, often with advice from others more knowledgeable in engineering techniques than I, I think we all bear similar scars!

With a taper that looked as though it had been attacked with a cold chisel, a sheared woodruff key and deformed keyway and circular gouging on the shaft where the gear sat on the shaft, I didn't think graunching the whole lot back together, with more torque and 'Loctite' was a good idea. I had also shortly afore this had the mentally scarring task of trying to dismantle a Duke motor that had let go in similar fashion to mine and had been 'rebuilt' using a bastard file to remove the 'rough bits', Loctite 'Stud lock' to hold it all in place, on the taper, keyway, between the gear and shaft and on the nut threads. It took heat, pipe freezing spray and 3/4" drive air hammer to part the bits!

Whilst I'm content to use 'alternative' parts, I try with my limited ability to keep the mechanicals safe, I have lost to many friends to mechanical short cuts or expediancy. A good wash with a reputable shampoo and then some wax polish once in a while is about as far as my concours finish goes. Trailering an 'immaculate conception' to shows; well, all the best, it just isn't my idea of fun.

Dave Roper's blog and machine preparation seem comfortable to me.

What ever you do Adam, I trust it serves you well and you can get out and ride the wee beastie. Bob, thanks for moderating the site and Stewart, I hope the 450 is still with you, as mine is with me.

Slainte, Bill.

[StewartD]

Hi Bill,

The 450 is long gone. I bought it in 1979 and I think it was sold off in about 1990. I was inspired to buy one after visiting the U.K. and Isle of Man in 1978. There were many of the yellow singles around at all the race meetings we visited, but they were pretty rare down under. It was my only transport for about ten years and never left me stranded.

The Mach 1 is enough to keep me busy now. I bought this in 1973 for $360!

I couldn't find the Dan Roper blog you referred to; can you give a link?

Cheers,
Stewart D

[themoudie]

G'day Stewart,

'78! That wistful look in the eye says it all! I had just finished college and was a one man band forestry contractor. The Duke went to the Manx GP that year. Going again this year to the Classic TT, not sure about the tinsel, but that's probably what's required to keep the gears oiled and air in the tyres.

Here is the link to Dave's Blog: Dave_Roper_Blog

I hope you enjoy it and the Mach 1 keeps you occupied.

Good health, Bill.