yamaha tzr50 problems

[wolfspirit]

Ive had this bike nearly two years. A couple of weeks ago the piston rings broke in it. Replaced the piston, rings and gaskets and cleaned the barrel out which hadnt been damaged. yesterday took her out to make sure she was running right and kept the revs and speed down for about 30 miles to get her run in, then reved her up and when she hit 8 thousand rpm she stalled herself but kept rolling. she started easily and away she went a while later she went over 8rpm but stalled again when she dropped back under 8thousand. she started again easily and when she hit 9 and a half thousand rpm i slacked off the throttle and she stalled and locked the back wheel throwing the back end all over the road. she had stalled but i pulled the clutch in anyway and threw her down the gears. she went into neutral but when i tried to put her in first she refused and did a lot of crunching and refused to go in. got her stopped and she refused to start for a while but eventually did. didnt rev her past 7 thousand after that in case she threw me again. Anyone any ideas on what could be the problem?

[Cynic]

And of course you measured the barrel didn't you? as ring failure is most common when the bore has worn.

Sounds like you have busted rings again, or worse a few bits of ring have got down into the bottom end. Either way your pulling it down again.

Feel free to introduce yourself in the new members area, you will get a lot more help that way. Note the sig.

[Airhead]

could be just heat seizing with the 'new' piston, really 30 miles and you're revving to 8k plus, is that recommended practice for this bike?

[Cynic]

They run to around 12k possibly/more than likely even more paul, they are ridiculous.

[wolfspirit]

she runs to 12 thousan d but ya can push her a wee bit more. 8k is just ordinary speed for her its nat really that much revving to be honest

[Cynic]

So did you measure the bore?

[wolfspirit]

no not yet i havent had a chance to get near her yet