[herman]

Started disassembly on the basket TL 250 project and everything went fine until motor disassembly. I knew I might be in for trouble when I pulled the points cover and found a rusty ign. plate. After the end of the camshaft snapped off with the ignition advance unit I knew it for sure. Still, I kept going.... removed all fasteners for the top end (there sure are an odd assortment of them), and tried knowing it wouldn't go easy, removing the head and cylinder. Other than a smal amount of movement at the base of the cylinder, the thing won't budge. I tried the usual slight prying and tapping with a rubber mallet with no luck. I really don't want to inflict any more damage, so I'm wondering what you folks might recommend. I've heard submersing the motor in ATF might help. Heck, I'd whiz on a spark plug if I knew it would get the job done!

[chewy]

Are you sayig the piston is siezed? have you got the head off?

[MotoVintage]

the dowel pins are probably stuck, just need a bit more force, try side to side with your rubber malet, make sure all the bolts are out, not sure on that model but honda hides head bolts under the valve cover

[Stecks]

Heck, I'd whiz on a spark plug if I knew it would get the job done!

Spark Plug - The spark plug is quite simple in theory: It forces electricity to arc across a gap, just like a bolt of lightning. The electricity must be at a very high voltage in order to travel across the gap and create a good spark. Voltage at the spark plug can be anywhere from 40,000 to 100,000 volts.

Not sure I'd whiz on that as a first port of call...

Ease it fluid and a firm approach with a rubber mallet... but you wouldn't want 100,000 volts any where near your whizing equipment...

[jon v8]

I think Moto Vintage may have a good point here,the 250 motor in my old Fraser had hidden head bolts - nearly caught me out when I took the top off.Be worth having a good look around before applying any force........

[herman]

Thanks for the advice. I' have a couple of days off starting tomorrow and I know exactly where to look for a hidden bolt. The microfische on bikebandit shows a nut under something called a sealing cap that is the same as the other head nuts. Under this cap is an O ring. I should have known......

[herman]

Yep, there was a hidden 4th nut under that plunger and once I removed it, things came apart nicely. Although I found rust on the breaker plate and camshaft end, the top end lookked pretty decent. Quite a bit of carbon on the piston crown and some ring wear. Looks like the partially stuck intake valve caused the lack of compression. Oh well. Gonna freshen her up with new piston/rings/valves anyway. Gonna need a camshaft, however. Question: does the XL version, same year, use the same camshaft?

[ocezam]

herman, on Nov 28 2009, 12:02 PM, said:

Question: does the XL version, same year, use the same camshaft?

I wanted to answer no they aren't the same (shouldn't the TL be tuned for more low end operation?) but according to BikeBandit http://www.bikebandit.com/houseofmotorcycl...e-tl250/o/m9274 The XL250 and TL250 share the same camshaft part number: 3837387-001.

With this in mind, the only engine differences that I know of are the TL has lower, and closer range, 1st, 2nd, and 3rd gears and it has magnesium side covers.

Bike Bandit is a great reference for checking old part numbers. You need to register and get an account to save machines you are interested in, then it makes comparisons easy.

Kent

[herman]

I'll do that. Thank you for the replies.

Herman