Kawi2strokes.com Forum

I'm about to do the top half of the motor on my h2a, going to have the cylinders vapor blasted the mechanic asked if I was going to change the crank seals in the bottom half, I wasn't planning on messing with the bottom half of the motor but he mentioned the bike is over 40yrs old and the rubber on the seals could brake apart and seize the motor. Should I replace them? Their are no leaks from the motor but now I'm worried. Thoughts?

You can do a leakdown test and find out the condition of the seals: http://www.kawatriple.com/cranksealtest ... altest.htm

It really is true that there's a good chance the seals are not in good condition. Getting the crank rebuilt will also allow you to replace its bearings. There are a couple well respected crank rebuilders in the vendors section of the resource site... Charlie Smith in the east, and Dave Singleton out west, as well as a few others.

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If it surges, that's normal, upshift.

Even if they are good now, they probably won't be in the future. Some are lucky and 40 years seals are still good, but most are shot.

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Twist the throttle, tilt the horizon, and have a great time. What triples are all about...........

Bad bearings can do bad things to the bottom end when they fail.

Good mechanic to mention that. Just wait till you see your output shaft gears and shift forks. $$

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Current bikes: H1 69,71,72,76 KH 500, H2 72(2),73,74,75(3) , 77RD 400, 08 KLR 650. 76 KZ 900, Yamaha RZ 500, ihave so many triples gave up listing them.
Have seversl tons of H1/H2/S parts for sale, http://www.triplestuff.net dhg1337@gmail.com

FYI I shot you a PM with some information. I will be glad to help you with this build. Even if you choose another builder please feel free to give me a call with any questions whatsoever about the crankshaft, condition, options, etc...

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Crankshaft Testimonials viewtopic.php?f=25&t=7593

"Let's keep your crankshaft great!"

I would do it now and be done with it. And then once apart, you could have the entire motor vapor blasted [cases, cylinders and heads].

I did it on my recent H2 project.

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H2B..... H1E..... Z1B ..... RD350...... X6 Hustler..... TS250.... CB750 ..... CB550...... and a Bomber!!