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Boring of cylinders


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I have a 2002 banshee that I am rebuilding my first one recently melted a hole though a piston and melted aluminum in the cylinder so I had a buddy of mine say he had a shop that would do a bore and hone job for me cheap so I traded him some ice racing tires that I had and we called it good. He said the shop bored it out .10 and I bought a piston kit. Then he called me the other day and said that the shop had a problem with my cylinders. He said that they can not get two of the head studs out of the cylinder to hone them. Was told the cylinder were going to be put in an oven heated slowly and them try to get the studs out. My question is he bs'ing me and just has not done my cylinders or do you have to remove the studs to do a hone job. Thanks for the help just curious because it has been 6 or 7 weeks he has had my cylinders and still have not got them back.

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wasn't aware you could bore, and hone nikasil cylinders. I noticed you said aluminum in your cylinders. x2 on finding the reason for failure, or it will be a repeat of what you already have at the moment. I learned my lesson with local shops boring, and honing cylinders. maybe a few good ones in your area, but none in mine. to me its bhq sponors, or bust.

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I believe the issue was a very lean mixture I have pro circuit pipes and boyseen reeds uni air filter. The carbs have 270 main 25 pilots which on the lean side to begin with and then it was 20 degrees outside in the winter so that leaned it out even more. I only had the banshee for about 1 week or two when this happened I traded a 426 dirt bike for it only had 500.00 into it. The guy who owned it before was running it with the idle screw out of the carb and could not figure out why it was not running good it was sucking air straight in the side of the carb. Also the rad reeds have dual stage pedals and one of the bottom reeds broke which would have been sucking air as well. Did not discover this until I took everything apart. Also the bike was a stock bore but had namura pistons in it and the stock head was pitted. Any input or disbelief of why this happened it greatly appreciated I'm fairly new to the banshee world. I own two this is my first rebuild of one.

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Expensive learning curve on tuning and boreing. Probably should have been about 320-330 on main for those temps.

A good machinist would have the pistons before boreing so they could be accurately honed for final size.

 

Shop I use had RM cyl bored and shipped back 6 days from when I dropped it off, just saying

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Expensive learning curve on tuning and boreing. Probably should have been about 320-330 on main for those temps.

A good machinist would have the pistons before boreing so they could be accurately honed for final size.

 

Shop I use had RM cyl bored and shipped back 6 days from when I dropped it off, just saying

This is key......most don't realize it but there ARE differences in the same size pistons.......why do you think builders often bore/hone cylinders and send you the pistons marked RIGHT/LEFT.  That is because they are bored specifically to the size that they measured the piston at.

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