440 big bore kit

There seems to be more and more members appearing that are racing the ZXR400 so i've created a special section just for you to show off results, discuss meets etc etc.

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WACEY
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440 big bore kit

Post by WACEY »

Hi lads, Does anyone know where I could get my hands on a 440 big bore kit.
If anyone knows of a company that does them or if there's one for sale let me know please!

Thanks
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masterofinsanity
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Re: 440 big bore kit

Post by masterofinsanity »

Don't forget people there is more to the zxr400 than this forum... check out www.zxrworld.co.uk also.
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mike684
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Re: 440 big bore kit

Post by mike684 »

Hope you're not one of the lads running in the Scottish championship!! :smt001 I had my 1st race meeting a few weeks ago and was disapointed to hear some of the regulars are grumbling about cheating, ie.440 engines being run in the production class....... :smt018
Respect it, but if you're scared of it, get off and let someone who's got balls have it instead........
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Re: 440 big bore kit

Post by carlfzxr »

It`s the same at every club mate, they should limit F400 to 70bhp in every club across the country. Just like minitwins do with the 72bhp limit.
maverick32
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Re: 440 big bore kit

Post by maverick32 »

Hi i run in the scottish production championship and to my knowledge there might be one person running a big bore kit, but not 100% sure.
You could always pay the money to have the engine checked, see Dougie :smt014
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Duane
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Re: 440 big bore kit

Post by Duane »

We have the same amount of whinging here in Oz, yet no-one has put up the dollars to protest. Mind you there are a couple of zxr's that are bloody fast!
I am currently researching if it is leagal here to run 0.5 oversize. Our GCR's say 2% tollerance, which I guess is 408cc, a 0.5 kit by my calculations would be 406cc making it within tollerance but I want this officially confirmed first.
Cheers.
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Ballsout Racing
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Re: 440 big bore kit

Post by Ballsout Racing »

A 2% tolerance on bore size will allow up to approx 412cc, so a +1mm piston can be used :smt002 :smt001
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Duane
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Re: 440 big bore kit

Post by Duane »

Sorry I should have stated that the tollerance is for "engine capacity" not just bore size. eg, a 100cc could be 102cc.
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murray#36
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Re: 440 big bore kit

Post by murray#36 »

It would'nt be a number 14 would it??? That is currently on ebay....Maybe he's selling it because everyones on to him...!
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stu71
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Re: 440 big bore kit

Post by stu71 »

Just a quick one ballsout you say you can use 1mm oversize pistons but in the rules it states its on the maximum rebore to the manufactors rebore size (.50) only, not the engine capactiy, so if you put 1mm ones in it's illegal ? Stu
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Ballsout Racing
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Re: 440 big bore kit

Post by Ballsout Racing »

stu71 wrote:Just a quick one ballsout you say you can use 1mm oversize pistons but in the rules it states its on the maximum rebore to the manufactors rebore size (.50) only, not the engine capactiy, so if you put 1mm ones in it's illegal ? Stu
I didn't say 'you can use', Duane was talking about his series allowing a 2% tolerance, I read that asbore size, he corrected me saying it was on capacity. You're right, where rules only allow a manufacturers overbore, the ZXR400 is +.5mm, the FZR400s will be +1mm and the Honda 400s nothing. Bemsee SBK400 rules for 2006/7 allowed a 2% tolerance on bore size which effectively allowed all the 400s similar maximum allowances as the manufactueres allowance for the FZR of +1mm, thus trying to make it 'fair' for all 400 irrespective of the manufacturer :smt002 (and stop the moaning :smt002 ) There are now +1mm pistons available for the ZXR400, but they really make very little difference to peak power :smt002 and affect the tuned engines in other ways :smt002
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stu71
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Re: 440 big bore kit

Post by stu71 »

lol not moaning just wanted to make sure there wasn't a loop hole in the rules :smt002
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Ballsout Racing
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Re: 440 big bore kit

Post by Ballsout Racing »

Not suggesting you were moaning, just explaining it all in detail so you understand the possible rules from different series :smt002

EDIT, while I'm at it, why on earth is someone asking about 440 kits in a racing forum, I can't speak for racing outside of the UK, but I'm pretty sure there is no class of 400 racing that allows 440cc in the UK ???

PS, I know for sure that there have been some 440cc race bikes out there though :smt013
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stu71
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Re: 440 big bore kit

Post by stu71 »

Ballsout Racing wrote:Not suggesting you were moaning, just explaining it all in detail so you understand the possible rules from different series :smt002

EDIT, while I'm at it, why on earth is someone asking about 440 kits in a racing forum, I can't speak for racing outside of the UK, but I'm pretty sure there is no class of 400 racing that allows 440cc in the UK ???

PS, I know for sure that there have been some 440cc race bikes out there though :smt013


And i thank you for explaining it to me Balls (thats where my brain is half the time) :smt003
Here's a little idea when i did autograss racing (cars) if they thought you was cheating you could put the money up for a set of gaskets and the cost of someone stripping the head off it, it was all marked up at the track, and if you was found to be illegal the owner had to pay the money for the stripdown and banned for 2 years, now i know that is a bit extreme but everyone strips there engines down at the end of the season for a refresh (normally) so if it was maked up with a dremmel it would last till then, and if they said oh it went missing or something daft, they would automaticly get a year ban ? (like drug test in athletics) P.S. i come secound in class one year, and the following year he did get banned with the same car B*****D lol
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billy big skid
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Re: 440 big bore kit

Post by billy big skid »

I regularly race against a Honda with a big bore kit.

I don't mind though, because i keep beating him. :smt003 :smt002
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