spike Posted August 1, 2006 Report Share Posted August 1, 2006 I'm thinking about boring my carbs but i would like some feedback before i take them to the lathe.. Anybody ever tryed it? Oval bore or round bore? Is there a big difference? thanks. Quote Link to comment Share on other sites More sharing options...
spike Posted August 2, 2006 Author Report Share Posted August 2, 2006 i guess i'l have to give it a shot anyway, Quote Link to comment Share on other sites More sharing options...
bansheeseat$$ Posted August 2, 2006 Report Share Posted August 2, 2006 I tried some 28's taper bored to 29.5 the idle quality was crap but wide open they worked great.My .02 cents Quote Link to comment Share on other sites More sharing options...
rkc Posted August 2, 2006 Report Share Posted August 2, 2006 (edited) i guess i'l have to give it a shot anyway, Hey spike, I had a similar post to yours I didn't get a responce either. You can do a search to find out more about boring. I'm going to try oval boring (27mmx29mm)and I know you have to be careful not to go to wide because of air leaking around slides effects the idle (thats what I've read anyways) On your search you will find some guys who know something about this. pm them and they will be glad to help you.Let me know how it works out for you! Edited August 2, 2006 by rkc Quote Link to comment Share on other sites More sharing options...
spike Posted August 2, 2006 Author Report Share Posted August 2, 2006 thats what i was thinking too, i'll give it a shot next week if my boss approves,will keep you guys informed Quote Link to comment Share on other sites More sharing options...
rkc Posted August 3, 2006 Report Share Posted August 3, 2006 (edited) thats what i was thinking too, i'll give it a shot next week if my boss approves,will keep you guys informed hey spike, since you're modifying your stock carbs I'll tell you what I'm trying this weekend I have seen alot of posts talking up the benefits of a flat slides and d slides. What I got out of their posts is that there is some negative side effects of having a round slide.The theory goes that air will stream in at a higher level(front cut out on round slide)then hit a wall(the back lower part of the slide) causing downward air pressure and turbulence occurs adding to air restriction (kind of like wind that gets diverted by a corner of a wall making little whirl winds)I think thats why flat slides are used(not positive though).I came across another product ufo's, basically to fill in the hollow wind tunnel up inside the round slide. I don't think it cures all turbulance because it just eliminates some of the area up in wind cavity leaving some lower wall exposed(back of round slide)plus there 60 stupid bucks.So I had a idea that might make a smoother air transfer under the slide and maybe even cause some velocity.I'm going to shove the right diamater cork into the bottom of the slides(corks used to be used for floats in carb bowels) and use high temp silicone to hold it in place and it won't ruin your slide(if it doesn't work). Then I will cut the cork to follow the lower edge of the slide. 1st by following the front cut out then chopping the cork that extend below the bottom of the slide. After that I'll smooth out the cork with fine grit sand paper and maybe sand a smooth groove from top to bottom, front to back to try to create a little more velocity.Then clean well.I picked up some cork stoppers today w/ 1" dia. I was able to find two that were dense(at least visibly)so they had no air pockets characteristic of cork. There has been tons of study on air flow, maybe some roughness is good but walls aren't.Should be a fun project.If you want I'll let you know how seat of the pants test goes! ps. oh yeah you'll have to drill a centered hole through the cork for the needle, small as possible w/no dragging on the cork. You also need some small slots cut in the side to accommodate guides in carb body.razor blades might work for that . I'm going to get longer needles too. Edited August 4, 2006 by rkc Quote Link to comment Share on other sites More sharing options...
gregbowler Posted August 4, 2006 Report Share Posted August 4, 2006 I hope to cork doesn't fall out and eat your top end :ermm: Quote Link to comment Share on other sites More sharing options...
FireHead Posted August 4, 2006 Report Share Posted August 4, 2006 I have bored a few sets of carbs and had a set bored. White Knuckle bored a set for me and they work ok, but they are a little tougher to tune. The sets that I bored were ok as well, but never liked to cold start. I would just buy a set of carbs that are the size you want unless you just want a project to do. :baseball_mitt: Quote Link to comment Share on other sites More sharing options...
strokersquid Posted August 4, 2006 Report Share Posted August 4, 2006 i have a set on a street rz bored 28 to 29.5mm and they are the cats ass but they were set up by dale alexander . i have a street rg500 suzuki bored 28 to 30 flat slide and the bore is slightly bigger than he slide so it does leak some air by but it too far outperforms the stock. as for the rz im told unported motors dont do as well with the bigger carbs and this is the best compromise. probably true of banshees too. Quote Link to comment Share on other sites More sharing options...
sredish Posted August 4, 2006 Report Share Posted August 4, 2006 The 40mm on my TRX is now bored to 43.5mm. Works great, came out great. Boring is a very easy way to get the power out of it. No sense in paying all that money for new carbs when you can bore them out a little. Quote Link to comment Share on other sites More sharing options...
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