Beast's Yamaha DT200 '96 - all good :)

[Beast]

ok so the DT has been going strong, and i have been having a hoot, I've just been running around on pre mix but low and behold on the way to work this morning my low oil light on the injection reservoir came on!!!!
so i guess the oil injection is working after all!!!!

what is the best way of verifying i am getting enough flow out of the pump before i start putting straight unleaded in her again?

[MRD]

Just check the pump stroke and then cable adjustment, you can run the bike with the pump cover off and hold it at half throttle and watch the pump to make sure the piston is moving in and out.
If you want to be sure oil is coming out while you have premix in the tank and the bike running just pop the hose off the carb and see if oil is comming out keep a finger on the pipe the hose come of so the bike does not suck air and rev out.
I had a look through a service book here but for some reason it does not list the pump's stroke think it would be around .20 to .25mm minimum. If you can see if someone has a workshop manual to check that for sure.

[Beast]

BUP BOW!!!


The DT is stuffed again.. well sorta
it did an oil seal to other day.. no biggy, just a output shaft seal (behind the front sprocket) but the bugger won't start (not i was having troubles prior to replacing the seal too)

Last few times i have got a bit of a run up and clutched it down a hill. starts up and runns fine, but for the life of me i can't kick it. After the run home the other day not even a decent length clutch start would make it fire.

it feels way down on compression, can push it along in gear and the motor spins, and turn the flywheel with two fingers

I shall endeavor to take the barrel off and have looksy
but it had been running quite well

i'm assuming the ring are shot

[Gonzo]

Have you worked out how many hours / km since the last piston was put in?

[Beast]

didn't find the paper work...... but i would think a few, maybe 7,000 but that is just a rough guess on then number of bottle of oil i have bought

[Gonzo]

That's a lot more than I thought you'd have done
I reckon you're rings are due for replacement.

I've only put about 20 hours on my smoker since the rebuild

[Beast]

well maybe less
i'm only guessing.. say 5,000 maybey
there would have been about 3000 in commuting since the k has been off the road.

[bing]

Time for....

[Beast]

i reckon i'd find away to break it. the ONLY bike i haven't killed is the 1400

[Nero]

BUP BOW!!!


The DT is stuffed again.. well sorta
it did an oil seal to other day.. no biggy, just a output shaft seal (behind the front sprocket) but the bugger won't start (not i was having troubles prior to replacing the seal too)

Last few times i have got a bit of a run up and clutched it down a hill. starts up and runns fine, but for the life of me i can't kick it. After the run home the other day not even a decent length clutch start would make it fire.

it feels way down on compression, can push it along in gear and the motor spins, and turn the flywheel with two fingers

I shall endeavor to take the barrel off and have looksy
but it had been running quite well



i'm assuming the ring are shot

Your furked oil seal might be preventing the crankcase from drawing enough fuel air in through the carb to actually start. I'd look into that first.

[Beast]

yeah me and frog thought the same thing at a strech... but no such luck.
i've been hit by flu and havn't got the barrel off yet, i may have a crack after work tomoz

[Beast]

[Sizzler]

Purely an uneducated guess- oil rich, fuel lean.

I've seen a few two-stokes destroyed by people thinking that more oil is a safer way to go; The worse that can happen is you have to change the plugs more often, right?

But more oil in the mixture means less fuel, and this causes the motor to run hotter, down the road to the dreadded sizure.
Too much oil can also clog the rings (they move slightly on the piston), this could cause the blow-by you can see in the picture.

That is my thoughts. Now someone tell me how wrong I am.

[beau]

I'd agree with that Sizzler.... and your theory is backed up by the fact that Beast was running pre-mix under the assumption that the 2T oil pump wasn't working, when it appears it was.

Time for a piston and rings and a light hone of the barrel I'd reckon

[Gonzo]

Nah, she'll be right. Just add more oil