Heat seizes...

[a.j]

...had a nip up sunday. I knew it was coming mind, the engine starts rattling & gets louder & louder like someone indiscriminately tapping a hi-hat on a drum kit. It has done this sporadically for years now when on a long run, but only when it decides. I can go 70 miles plus somedays & nothing, yet sunday did 14 miles & she locked. I've got a mildy tuned 200 slightly & running a 22 mm delly carb..

Any suggestions?

[drunkmunkey6969]

what's the ign-timing set at?

[a.j]

what's the ign-timing set at?

er.....

[Knowledge]

Have you cleaned-up the barrel and piston after the previous lock-ups?

[a.j]

Have you cleaned-up the barrel and piston after the previous lock-ups?

I'll start tomorrow & take a pic or two.

[J1MS]

Cant wait to see the pics.....seizing for years.... .....

[Knowledge]

I always manage a sharp intake a breath and walk away when people say "It nipped up last week, but it seems alright now".

Once you get the skidmark-of-doom down the side of your piston, you need to get it off. The sieze mark doesn't hold oil like an unblemished piston, so the piston is FAR more likely to seize again, and next time you might not be so lucky (perhaps overtaking a lorry).

Get the head and barrel off the piston, polish the ali off the inside of the barrel and remove all the skidmark from the piston. Then, rough-up the surface of the piston in the troubled area so that it will hold oil. You can even use a file to mark it up.

Go on, do it. You know it makes sense.

[a.j]

Right. Got the barrel off & the marks are obvious..





Under the long barrel stud nearest to the camera the piston is particularly marked. You think a barrel hone is wise?

I'm half bloody useless at spanner work & always avoided it, but I'm determined to be a little bit self sufficient.

[Rude De]

Did you forget to add oil to the gas? that piston and barrel look bone dry
hone it and rering it

[lifes a drag]

i cant belive people advise using a piston after its siezed , hone the bore if its lightly siezed but bin the piston and buy a new one . surley if your taking a file to a piston its gonna take more off one side than the other therefore changing the shape of the piston . i know people on here are gonna start saying they do it every time they sieze a bike and they never have problems but for me your just asking for trouble . im not saying im an expert but just using common scence , ALWAYS replace knackerd parts with good quality new parts , the best you can afford , im sure you can afford a new piston if not just for pease of mind . im from a school boy moto x background where the rings were changed every 5 hours and piston every 10 so i supose thats where i get it from but our crossers never siezed