Messages

Enjoy the dirt with your sons! I've noticed that All Balls stuff is mostly Chinese made stuff, for what it's worth. I bought some crank bearings/seals of theirs that were Koyo (I'd never use a Chinese crank bearing), but all the other wheel and steering bearings have been no name Chinese.

That's great.

You'll love the KTM. I did a similar last year and bought a 2005 KTM 250EXC 'for my son'. It is an absolute beast and a blast on the trails. Almost too much bike for tight trails, but hey I don't want to sound like a wimp.

Wing cars and GNXs. That's awesome.

What Mark said about pulling the pump cable wide open. Sounds like you're getting closer to PWK bliss.

I do believe the earth needs more two stroke smoke. Carry on and do your part.

Good looking bike! Enjoy the refurb.

Happy Birthday. Thanks for your efforts connected with this forum.

Congratulations! Time to ride the piss out of it.

Buy an RZ with crappy carburetors Steve! It will be fun they said. I pray the PWK's treat you better.

Well ok, that is fun.

As an update to this journey, I verified the compression gage accuracy at work so 90 psi was right. Pulled the top end off and found lots of little scratches etc. on the piston and cylinder walls. No canyons or anything like that, just not as it should be. Pulled the piston off the rod and what really got me was the area on the pin under the bearing. Instead of bright and shiny, it looked like it had been sanded to a dull finish. This tells me that the whole inside has processed a lot of sand, and I need another total rebuild. Crap. This motor had maybe 30 hours on it. Hard lesson learned about filtration and making sure all is right on the intake side. About a $500 bill for bore/crank and all associated parts. Thanks all for the help, and to 1976RD400C for the reading on your IT175 that pretty much said mine was done.

I have one of those IT175's. Just out of curiosity, stock cold engine, no oil, hasn't ran in months, 150psi. They are kind of a high-performance motor.

Well thank you for the comparison! That's certainly telling. Sounds like new top end here we go. And maybe new bottom end. Crap. It was a new crankshaft.

Thanks for the replies so far. I work in a test lab so I'll check the gage and make sure it's on. Probably also do a hot test. Thanks Mark and JKV45 for the numbers to compare with, some depress me and some don't. The bike runs ok, but my gut tells me I'm looking at a full top end treatment.
I think the foam filter element wasn't fully seated or was previously crushed and thus all the sand. Northern Michigan trails are full of (unwanted) stretches of pure sand.

I have a 1979 Yamaha IT175, rebuilt the motor after buying it. Top end got new piston and rings and a honing because it wasn't too worn (yeah I know, should have bored it). Ran ok for a summer. This week I went to drop the carb needle a notch and during that found an alarming amount of sand in the intake. Obviously I need to figure out how it's getting in there, but I feared for the health of this motor and did a compression check. 90 psi cold. I have no idea what it was right after the rebuild. Is this number too low to hope for another season? What numbers would you guys expect for a bike like this at its best? I realize it probably should be tested hot as well. Thanks!