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Motor experts, help please, rod question

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OK so the other day i tore down the 150F's motor to put a new topend in and have the valves lapped. Well, I was removing all of the old cylinder gasket today and i noticed that my rod is bent quiet badly. My dad seems to think that it came from the factory like that since there is no evidence of piston collision with the valves, but I'm 99% sure that i somehow bent it. When i parked the bike and began the tear down it ran great, it just had a little blow by and i figured two years on the stock topend it prob needed rings and/or piston. Turns out that the piston is in really good shape, just the normal carbon build up that i got all cleaned up and looking next to new. So i really have no idea how the rod could be bent? Any ideas? It looks like im going to have to replace it, but it ran so good before...The only thing that i can figure is when i hydrolocked the motor last spring, but i rode it all through the summer without any problems :thumbsup: I'm not really sure what my question is, other then, why did it still run with the rod bent? Also, could it have been the hydrolocking that bent the rod? Right where it's bent its very blue, like it was superheated or something, if that makes any difference, thanks for the help guys

-Chris

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Sounds like it's time for a stroker kit!

Or, CoeShow on here that builds big bore CRF150s - he might have a good CRF150 crank he'd be willing to sell you at a good price. (this would be the hot ticket if he has any!)

Or I'd be happy to help you out - think I can get you a new one for around $200 + bearings which are right around $25+ ea and you need two. (guessing on the bearing price)

How did you "Hydro-lock" your engine? And what makes you think it was actually hydro-locked? Did you sink in a stream, or put way too much oil in or something?

Mike

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Well, i guess i should mention that this bike will be for sale as soon as it's put back togther, so cheaper is much better!

Can i not just get a rod kit with the bearing, change it out, and then be done with it?

I rode it through a pond and sucked water in though the intake and locked the motor up. I took the plug out afterwards and kicked all the water out. She fired right up on the first kick, so if it did bend the rod, i dont think it hurt it's performance at all. These little motors are tough as hell, so it'd prob be plenty happy with a bent rod :thumbsup:

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so it'd prob be plenty happy with a bent rod :thumbsup:

I wouldn't be plenty happy with a bent rod if I was the guy buying your bike.. :ride:

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Rest assured, Im not going to put the thing back together with a bent rod. The smily was there to infer sarcasm :thumbsup:

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chondamx,

I have a number of very low hour used CRF150 cranks. You can get a rod kit. I checked Ron Ayers but there must be a problem. The price for the rod kit is $166.00, while a complete new crank is $176.00?

By the way, water injestion will bend rods EASILY! Even a major gasoline flood out can bend the rod.

If you're interested in one of my low hour cranks, please PM me for details. I can save you a bundle.........

Good luck and ride safely.

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Shot yah a PM Coeshow, i think i was a bit confused when i sent it, though, feel free to clarify :thumbsup:

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No, I don't think so, I'm 95% positive that I bent it when i hydrolocked it. It is intresting how the whole rod is a different color after the bend then before it, though. OK guys, i have another question. Im putting new rings in it and I'm having the clylinder honed; do I need the standard size rings or the .25 oversized ones? I'm guessing that i only use the OS ones with the .25 OS piston, correct? I'm using the stock piston, so stock sized rings? Sorry for all of the questons, this is my first topend job on the 150.

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yes use your std piston with std rings. honing only deglazes the cylinder and doesn't take much material out.

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