175TS with 125S engine project

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George
Posts: 385
Joined: Fri Feb 14, 2020 2:51 am
Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Thu Mar 26, 2020 8:57 pm

Duccout wrote:George, there is a 125 piston on eBay that is listed as being 59.6 mm, I wonder if that would work in your engine? The barrel sleeves in these engines are very thick, so it may be OK. We need a 125 - 160 - 175 expert to advise!


I did see that, no rings and I would think impossible to find. 7.4 mm over size would make capacity 145 cc, perhaps a step to far. I cannot find any singles that use that size.
Think I will pass.
George Essex UK

George
Posts: 385
Joined: Fri Feb 14, 2020 2:51 am
Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Thu Mar 26, 2020 9:14 pm

Typing (brain) error should read 4.4 mm over size.
George Essex UK

George
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Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Sat Mar 28, 2020 10:07 pm

Another frustrating day trying to remove Oldham Coupling sleeve from bottom bevel shaft. No corrosion just very tight. Am I correct in thinking that sleeve should be a light push fit. Convinced previous owner must have hammered it in. Top bearing on bottom shaft is in poor condition and could have been damaged when assembling.
Plan A:
Remove crankshaft bevel (left hand thread). Somehow remove bottom sleeve circlip. Hammer shaft down hoping top bearing will support sleeve and shaft will move downwards. Can anyone confirm I am thinking right please.
Plan B:
Take a mini grinder to sleeve. Problem with this I would require replacement sleeve and would raise more questions,
1) are sleeves paired to couplings my shaft is 14.98 mm dia and sleeve has three green painted dots. Have not measured sleeve yet.
2) Will have to search for new coupling, hoping they come in different sizes
3) Are couplings same size for all narrowcase engines

On a positive note, removed clutch side cover and gears etc look in good condition. Tab washers and other parts suggest previous restoration, perhaps with re bore, high compression piston and sport head fitted to TS engine, Even the points look almost new.
George Essex UK

Duccout
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Location: Essex UK

Re: 175TS with 125S engine project

Postby Duccout » Sun Mar 29, 2020 7:21 am

AFAIK, there is the standard sized sleeve and one undersize (I know very little about small Duke engines though !) the sleeve should be a sliding fit and it is more usual to find that the shafts have worn slightly in use and require the undersize sleeve to take out play in the shaft. It seems that maybe the PO has fitted an undersize sleeve to your engine and forced it on.

I think that course number 1 sounds best, assuming that you can get the circlip off, and assuming that there is enough room beneath the bevel gear before it hits the crankshaft. Course number 2 is fraught with danger and would be very difficult to achieve.

There always seems to be a problem to overcome; just when you think that something is going smoothly, a fly appears in the ointment. When I took the barrel off my Strada I was pleasantly surprised, but when I tried to remove the piston, I couldn't get the gudgeon pin out, no matter how hot I got the piston the pin did not want to leave. I have never come across that before.

George
Posts: 385
Joined: Fri Feb 14, 2020 2:51 am
Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Sun Mar 29, 2020 7:01 pm

Duccout wrote:AFAIK, there is the standard sized sleeve and one undersize (I know very little about small Duke engines though !) the sleeve should be a sliding fit and it is more usual to find that the shafts have worn slightly in use and require the undersize sleeve to take out play in the shaft. It seems that maybe the PO has fitted an undersize sleeve to your engine and forced it on.

I think that course number 1 sounds best, assuming that you can get the circlip off, and assuming that there is enough room beneath the bevel gear before it hits the crankshaft.


Thanks for reply
Shaft flats look in good condition, makes sense that PO fitted wrong sleeve. Will try to move sleeve tomorrow. Have not got tools to split crankcase and not going to order anything while virus is getting worse. Plenty of other things to do
George Essex UK

George
Posts: 385
Joined: Fri Feb 14, 2020 2:51 am
Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Tue Mar 31, 2020 7:23 pm

The coupling sleeve is off. Had to get the Dremel grinder to it in the end. Cannot imagine how the PO thought hammering it on was a good idea.
According to my parts list coupling was available in three under size's to take up slack in shaft flats, as mine are not very worn I will measure and get coupling to suit.
Dismantled clutch plates and checked for wear. Look almost new and well within wear limits. Again pointing to previous re build.
George Essex UK

Duccout
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Location: Essex UK

Re: 175TS with 125S engine project

Postby Duccout » Tue Mar 31, 2020 8:58 pm

Well done. No-one said it was easy!

George
Posts: 385
Joined: Fri Feb 14, 2020 2:51 am
Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Wed Apr 08, 2020 8:39 pm

Update on restoration progress
engine stripped down except crankcase halves, that will have to wait till I buy special tools. I think this bike must have been owned by the same bloke that Duccout bought his bike from.
List of bad workmanship is growing along with list of parts required. Shims missing in gear selector box, used lock washers fitted with tab missing, self centering bearing in top bevel so worn balls fell out when I removed from shaft, clutch rubbing on cover shedding alli fragments and to make matters worse noticed filter lying in bottom of sump. Expect to change all bearings now. That's just some of the bodging.
Some polishing today to give my brain a rest. Start afresh tomorrow. Might see if I can make cam shaft lock tool and strip head. Who knows what I will find!
Bit of good news I have located used cylinder in good condition and suitable for re-bore. Pleased with that as existing cylinder had broken fin at base and would have spoilt finished engine. Contacted Piston King in Italy, they keep piston sets up to 55.6mm in stock with facilities to make wider over size. I will order when things get better in Italy and UK.
Stay in Stay safe
George Essex UK

Duccout
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Location: Essex UK

Re: 175TS with 125S engine project

Postby Duccout » Wed Apr 08, 2020 8:55 pm

Well done; at least it keeps us off the streets!

George
Posts: 385
Joined: Fri Feb 14, 2020 2:51 am
Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Sat Apr 11, 2020 1:29 pm

I have stripped head.
Good bits.
Rocker pins in good condition, valve stems and guides good, valve seats reasonable, springs minimal wear, exhaust and spark plug threads good.
Bad bits.
Upper bevel bearing housing loose in head. Strange but looks like housing worn more than head. Will replace housing, is it recommended to loctite in when assembling?
Rockers worn and will have to be replaced. Wondering if 1960s Mototrans same as Italian and same as 160 engine. Hoping Jon will be along sometime to confirm. If same would give me better chance of finding some or maybe Nigel will have some good used ones.
Cam showing some wear, think it will be OK to use, photos added, advice welcome, cams have slight wavy lines on peaks should I leave or dress with fine stone?
Enjoying my first Ducati restoration, well designed. Beginning to find out why Ducati's are expensive
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George Essex UK


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