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racing questions

Posted: Sun Sep 07, 2008 4:24 am
by don
i think is is in the right place,

iv been living in california for the last 7 years,i used to ride a zxr at home in ireland,
i want to race a zxr 400 next year in england or ireland ,
i have been racing here for 4 years now, 600s.
i dont have great knowlage about zxrs,
which model is best to race,
my bike is an 89 model,im not sure what shape its in now.
i think ill try to buy a race preped zxr,
what should i look out for,and which model
thanks :smt003

Re: racing questions

Posted: Sun Sep 07, 2008 4:53 am
by zimm
WARNING THIS POST IS A GROSS GENERALISATION BASED ON PERSONAL OPINION

once prepped as a racebike all the bits that differentiate between the various models arent fitted ..

eg,

engines.. pretty much the same from 89 to 2002 (or whenever they stopped making them) all capable of the same power
suspension .. well, you fit aftermarket stuff innit :)
airbox, will be junked for ram-air, works on both L and H
bodywork, most race fairings are L shape, but will fit an H ..
ignition, which has a better advance curve is a grey area, H's rev higher than import Ls (14,800 compared to 14,500) but UK spec L's rev higher still (14,900) .. not a lot in it .. and programmable ignitions to mate to an L loom arent going to break the bank, so again its kinda irrelevant.

etc etc ..

the H1's use a smaller diameter rear wheel spindle and different sprocket carrier, also a heavier swingarm .. also smaller headstock bearings.. maybe a problem ?

as for which is best H versus L .. the L is potentially a bit lighter.. but really there's not a lot in it .. i've had several of each and prefer the H's, (my racebike is an H1) no real reason why i prefer them .. maybe its just the shape of the tank and riding position, dunno, feels a bit more planted than the L4 i had .. touch more forgiving.. + its eligible for pre 1990 classes :)

ignoring the pre 1990 thing.. my pick of the bunch would be an H2.. seems a lot of folk run an L as a main bike and an H as a wet bike ..

just get one with a spec that suits you're level of riding, there's some outrageous HP claims floating about, but anything over high 70's is either bullshit or liable to need refreshing every couple of race meets.. i've heard people claiming 90+ bhp .. IMHO its bollox, RMKD built an uber trick zxr that made a genuine 82bhp (ish) they call it reliable, and it didnt blow up, but it did come apart a lot (apparently)

dont be tempted to pay extra for something based on an SP, you'll need the engine tuned anyway, and the suspension, so by the time you've done that the fact it started life with more adjustable forks and shock + adjustable cams, FCR's and a different CDI is meaningless.. course you'll still have the SP close ratio gearbox.. but just as many hate it as love it, and you'll lose it the first time the engine pop's or you fit a spare or whatever, unless you swap the gearbox internals over.

there's loads of info buried in the forum here ..

oh .. yeh ., Hi !

Re: racing questions

Posted: Sun Sep 07, 2008 8:11 am
by Davw
Hi Don,

I have just finished (if this is ever really finished) prepping a race bike from standard. I thought long and hard about buying a stock bike versus an already prepped race bike and there were times during the strip down and rebuld that I thought buying a prepped bike would have been simpler.

However - the more people I talk to about buying an existing race bike the more horror stories I hear (there are a few recent examples on the site here) At least prepping it yourelf you know the history and you know whether (for example) the fork internals really are K tech or whether the k-tech ones were stripped and sold seperately and you are left with standard forks and a couple of k-tech stickers!!

The other great thing about stripping the bike and rebuilding it is that the stuff that you will need to be familiar with at the track (wheel changes, footpeg changes, brake bleeding, pad changes etc etc) will be pretty straightforward as you will have done them before and will have the tools sorted for the job - that is what what I kept telling myself after a late night in the garage trying to work out what i was doing wrong :smt017

Good luck :smt001

Re: racing questions

Posted: Sun Sep 07, 2008 10:21 am
by will#224
Ive just bought 2 race bikes, Ive got a H1 and an L1, Zimm has given you the details about the spec pretty much, the H1 is a physically larger bike while to the L1 feels more like a recent 600 in terms of size imo.

I bought them both as race bikes as i knew the chap selling them, i know the spec ect to be decent, i'll be doing a lot more work to them before racing them next year. Both bikes cost me £2750 but i'll putting another grand into an engine/suspension refresh and will be adding quite a few more race parts and ridding them of some weight.

I think the price of some of the race bikes available at the moment is a little high so i'd shop around. For my £2750 i got 9 wheels all with good tyres, 3 fairings which i beleive to be worth over a grand new, all the road gear and enough spares to almost build a 3rd bike. No way could you build 2 race bikes from road bikes and have all the wheels and spares i have for the money ive spent. The suspension will always need setting up for your style and weight so it doesn't matter if its stock imo.

Re: racing questions

Posted: Sun Sep 07, 2008 10:49 am
by zimm
will#224 wrote: I think the price of some of the race bikes available at the moment is a little high so i'd shop around. For my £2750 i got 9 wheels all with good tyres, 3 fairings which i beleive to be worth over a grand new, all the road gear and enough spares to almost build a 3rd bike. No way could you build 2 race bikes from road bikes and have all the wheels and spares i have for the money ive spent
reckon my (bought as a non running roadbike) H1 will stand me at about 2k by the time it gets to a track, thats with stock suspension, no ramair and having built my own engine. but i do have an entire spare H1, 2 sets of bodywork (3 tanks) a brand new titanium beet system and a used micron included in that price.

easily another grand to be spent on forks, shock, ramair, .. nnn stuff, and i'll still only have 1 useable bike.

you got a bargain Will ! and you're right, there's some not particularly fresh or trick looking bikes out there with silly 3k+ asking prices ..


weird how the H is bigger, i think its because the tank is narrower it feels more compact and I can move around on it, I found the L bulky and harder to move around on.. but im an oddly proportioned 5ft 4" ..

me making an L4 look like a 750

Image

and on my H1

Image

Re: racing questions

Posted: Sun Sep 07, 2008 2:56 pm
by Davw
Agreed - you got a great deal - particularly as you know the history of the bikes - good luck

Re: racing questions

Posted: Mon Sep 08, 2008 6:31 am
by don
thanks for the help,what model is the sp ,what is sp,also what is the close ratio gearbox,
would it help to stick in a 636 rebuilt front end wheele and brakes,or would it be a bit to much.
thanks again.

Re: racing questions

Posted: Mon Sep 08, 2008 1:21 pm
by deviant
SP stands for 'Sports Production'. Basically a slightly more trick version of the stock bike, with a single seat as standard, different forks/shock, different cams and gearbox ratios. This thread is a good start...

http://zxrworld.co.uk/zxr400oc/viewtopi ... =69&t=3612

'Close Ratio' means the gaps between the ratios in the gearbox are smaller - so you still have six gears but they don't cover as big a range as the six gears in the normal bike. In effect, if both bikes are geared for the same top speed in 6th, the SP will have a higher top speed in first, then the other gears squashed in closer together.

The advantage is that because the gears are closer together you will be more able to keep the engine in the right rev range.

The disadvantage is that you will probably be changing gear more often.

I don't know what the actual difference in the ratios are, and as zimm has said, the racers on here seem to be divided in which they prefer.

Re: racing questions

Posted: Mon Sep 08, 2008 2:00 pm
by zimm
seems the short circuit racers dont like the CR box as 1st is V tall which buggers up the starts, whilst road racers like it as it gives you more choice of usable ratio's once under way..

im using an H gearbox, which is more evenly spaced than the L, which is kinda halfway to the SP compared to the H, IIRC 6th is the same on all the boxes and H and L share the same 1st too.