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Old 07-12-09, 09:05 PM   #21
RGV500
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Default Re: High compression piston kit

Does he do any work on the gearbox?

Any there any supertwins guys running into gearbox problems with such significant power increases?
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Old 08-12-09, 06:33 PM   #22
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A guy I know who races the roads here has his SV doing 84bhp with standard bore running high comp pistons,porting,cams,PC and a Hindle system. I feel the 80 bhp mark can be reached easily and safely. He raced his bike for a full season and never touched a thing nor had any problems. Im hoping to achieve high 70-low 80 bhp with mine for next season
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Old 08-12-09, 06:48 PM   #23
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Originally Posted by Dr.Tom View Post
A guy I know who races the roads here has his SV doing 84bhp with standard bore running high comp pistons,porting,cams,PC and a Hindle system. I feel the 80 bhp mark can be reached easily and safely. He raced his bike for a full season and never touched a thing nor had any problems. Im hoping to achieve high 70-low 80 bhp with mine for next season

I orderd my rods and pistons yesterday from the US, a guy on here SV race parts, his name is blair. Great price and very helpfull, the Carrillo rods are on back oder so wont get them till end January, went with the Wiseco 645cc High compression pistons. Are you getting your heads ported and cams re-profiled? If so who is doing the heads for you? I've priced it with a few people but I'm still looking around. Did you race here this year?
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Old 08-12-09, 06:53 PM   #24
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I orderd my rods and pistons yesterday from the US, a guy on here SV race parts, his name is blair. Great price and very helpfull, the Carrillo rods are on back oder so wont get them till end January, went with the Wiseco 645cc High compression pistons. Are you getting your heads ported and cams re-profiled? If so who is doing the heads for you? I've priced it with a few people but I'm still looking around. Did you race here this year?
The guy Im talking about ran standard rods and JOG Tuning done his engine work. I only done the Mondello rounds this year in the SS600 on my old R6 to get into the swing of things. I recognise your name for Cleggys site. If any engine work is being done Im gonna tackle as much as I can myself along with my buddys help(nothing I have built has blown up yet). im also looking into the idea of running the Hayabusa pistons to keep costs down. Must do more research into that though
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Old 09-12-09, 01:28 PM   #25
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Originally Posted by RGV500 View Post
Does he do any work on the gearbox?

Any there any supertwins guys running into gearbox problems with such significant power increases?
We havent come across any gearbox issues as yet and are running 90bhp on a dynapro dyno. The only thing Steve is now running is a new design of slipper clutch from Sigma as the original ones were getting excessive wear on the pressure plate due to the extra torque produced over stock.

We are now though running a Nova full close ratio box in his SV700 and trialing a new race generator which will help in reducing the weight off that side of the crank at high rpm. May go someway to saving a set of crankcases

We wont do any tuning work to them without adding carrillo rods. The stock items are just too weak ideally. One of them lets go and you trash the head at the very least. You just have to watch out for some copies that were floating around having been made by another UK based tuner. They are slightly out of spec (too short) and loose you compression and BHP. Not ideal!

The Hayabusa pistons dont give as much as the wiseco's. About 2-3bhp at mid to high rpm less.

Emmet - did you get my mail re the valve/headwork?.

Last edited by SV650Racer; 09-12-09 at 01:32 PM.
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Old 09-12-09, 05:58 PM   #26
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Emmet - did you get my mail re the valve/headwork?.
Don't believe I did, I've been on to that many people. The last email I sent you was requesting a quote for the heads gas flowed and valves with a 3 angle cut. I'll send the heads to you and pay for return postage. Cheers
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Old 09-12-09, 10:19 PM   #27
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Default Re: High compression piston kit

hi i cleaned my own heads up with a dremmel type machine and fitted a pair of kent cams power commander put it on a dynojet dyno and 1 hour later 79.8 bhp not bad easy to do the heads as well
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Old 09-12-09, 10:24 PM   #28
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hi i cleaned my own heads up with a dremmel type machine and fitted a pair of kent cams power commander put it on a dynojet dyno and 1 hour later 79.8 bhp not bad easy to do the heads as well
Well done,fair play. Did you match the exhaust ports to the exhaust using the Dremmel thingy or what did you do??
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Old 09-12-09, 10:26 PM   #29
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Default Re: High compression piston kit

Got some spare heads to give that treatment myself. I was thinking just polish up the inlets a few grades and finely radius the point in between the ports, same treatment to exhaust.

Exhaust doesn't look too bad a shape to start with, just bad surface finish, not sure how much you could smooth flow out without making port too big and losing velocity?

Probably better to keep it to a basic polish and clean up for me...
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Old 09-12-09, 10:47 PM   #30
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Well done,fair play. Did you match the exhaust ports to the exhaust using the Dremmel thingy or what did you do??
cheers just concentrated on the inlet side more than anything by taking a fair bit out and even taking a lot off the valve guide and knife edge the web on the exhaust side just cleaned it out a bit all in all got it from 72 bhp to 79.8 for the price of 260 i think for the cams and 60 for the gaskets i has got old of a load of shims as these had to be altered a lot even had to create a new shim table in the haynes manual as they didnt have the sizes wrote down i needed it has been raced for a season and half and is reliable.
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