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thai-ty

250 mono c/case work

7 posts in this topic

I've got a downloaded genuine 350 workshop manual. Once it gets to gearbox internals, splitting c/cases and c/shaft work etc, it says "take it to your local dealer".

I have 3 spare 250 mono engines and fancied rebuilding one from scratch as a spare.

1. I presume all workshop manuals available are the same and don't describe the above in detail?

2. Has anybody pulled apart an engine and can give me any pointers, pitfalls and what to expect, particularly;

# g/box cluster assembled in which side case?

# crank can come apart using a normal 15T hydraulic press?

# Big end presses out from which crank side?

# Any other things to look out for?

Cheers in advance.

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See if you can get a Haynes manual, they go through doing engine work in beginner-friendly wording (I have one for the earlier TYs, would be surprised if there wasn't one for the monos, too)

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I've just dug out the Yamaha "Owners Service Manual" I have for the Ty250n mono's, as you say it does not cover splitting the crankcases. II can't remember how far I took mine apart,(It was back in 1989... But I think I would have treated it just the same as any other vertical split case bike engine I've had apart.One thing I do remember is how strongly built they were,I think much of the engine was the same as the YZ motocross engine.

Perhaps a long term Yamaha dealer may have had the full dealer version of the shop manual, they must have had something for the dealers to use,especially for the YZ engines where full strip downs would be more likely. Worth E-mailing a few dealers ? This link to one on Ebay is the same as I have ;http://www.ebay.co.uk/itm/Genuine-Yamaha-TY250-N-Mono-1985-on-Factory-Owners-Shop-Manual-Book-TY-250-59N-/282690215346?epid=1623846152&hash=item41d1a65db2:g:sqsAAOSwDmRZ3gOL

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13 hours ago, jon v8 said:

I've just dug out the Yamaha "Owners Service Manual" I have for the Ty250n mono's, as you say it does not cover splitting the crankcases. II can't remember how far I took mine apart,(It was back in 1989... But I think I would have treated it just the same as any other vertical split case bike engine I've had apart.One thing I do remember is how strongly built they were,I think much of the engine was the same as the YZ motocross engine.

Perhaps a long term Yamaha dealer may have had the full dealer version of the shop manual, they must have had something for the dealers to use,especially for the YZ engines where full strip downs would be more likely. Worth E-mailing a few dealers ? This link to one on Ebay is the same as I have ;http://www.ebay.co.uk/itm/Genuine-Yamaha-TY250-N-Mono-1985-on-Factory-Owners-Shop-Manual-Book-TY-250-59N-/282690215346?epid=1623846152&hash=item41d1a65db2:g:sqsAAOSwDmRZ3gOL

Yeah, Thanks, just checked that link, which lead to another Ebay link for another w/shop manual being sold by bike book specialists which amongst the blurb states "everything except splitting the c/cases"....

So, c'mon, somebody out there must have split some cases and had a crank apart. Anybody?

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Hi Guy's

Hi TI,

Mail me on my web site for a link to someone who can help.

 

 Regards Charlie.

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22 hours ago, charlie prescott said:

Hi Guy's

Hi TI,

Mail me on my web site for a link to someone who can help.

 

 Regards Charlie.

pm sent.

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If anybody's interested, and like their workshop manual for complete teardowns, I have found out that the Pinky (4AJ?) 1990 on manuals show everything.

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