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Good morning. With the risk of sounding unhelpful (but actually meaning to be very helpful) I suggest you search the forum for how to increase your HP. Whilst the basic method involves doing the same things everyone has their own unique ways to achieve what the deem suitable. There is no 'one size fits all'. Probably the first question is to ask yourself why you want more power. Is it for racing, or the road. If its for the road, I would just buy a 600, if its for racing, I would buy one of the many race bikes already sorted and for sale. If its simply because you love ZXR's, have a limited budget and want to start tinkering, then goon on ya, but read all the info you can find, make your own conclusions and proceed with the the knowledge that you are tinkering with something the the Japs got pretty much spot on as is, and any fat oil fingers changing things will most probably lead to you buying a bus pass for your commute to work instead of your usual 25 mins scratch aboard your ZXR. Oh, and your limited budget will not be big enough and you would need a lot more that filter and exhaust swaps for 75hp. On their own your bike will probably be worse as the fueling will be out. Mine kicks out 72 and personally I wouldnt try to get any more out of it. 72 took many hours of my 'well read but limited experience'd head and hands to achieve.

Not sure about Sandybikes exhausts. They may be better than standard but I think they are built to a budget, but Ive never seen one myself.

Dont let my words of caution put you off, just be sure not to kid yourself that you can do (without hitch) what some people have spent many years perfecting. Most importantly, just read all the threads on this forum (and order that buss pass)

Is it just more power you want for bragging rights (?) or do you want it to be realistically quicker on the road?

If it's the former then don't bother, if it's the latter look at the forks and shock

Hi Mate, am no expert but to get my race bike to where it is has cost a fair few bob and a grand wont turn a standard 60 ish motor into a 75bhp motor....well not in my experience.
Sandybikes exhausts....never herad or seen one before, maybe there's a reason for that...well in the racing cirlcles that it.

Exhausts: Beet or MHP are good ones
Head work
SP Cams
Airbox

In all honesty if your tuning your bike to lets say 75hp and then your going to ride it on the road all I will say is that it may not last too long.
20 year old tuned engines can make them a little fragile and you may end up spending more on rebuilds and repairs than the original build itself.

If I had a budget then I'd probaly never race, I just spend then worry a little before spending a little more to make me happy then worry again..and so it goes on

Good luck tho
Jonesy

Search engine is your friend, but 1000 isn't going to get you there. Your not going to get 75 HP with going into the motor, and anyone that tells you that you don't have to re-jet after changing you exhaust system doesn't really care how your bike runs.

Sadly its not as simple as simply changing kets to suit the new pipe. Every change you make is one step away from the 'perfect' setup the makers reached, and as such you will need to spend dyno time dialling the carbs back in to get it working suitably. Sometimes you find that the change you made that 'in theory' should give a little more power, actually make the engine worse. I.e. less power overall, or a little more somewhere in the range with a nasty notch somewhere else.

As other have said, Beet pipes are good kit but cost a grand new compared to a £150 Sandy's exhaust. Theres a reason for the difference in cost (other than then titanium ). You need race lift adjustable cams and so on. If its just for the road, I would make sure the engine is in excellent standard order, and spend money on overhauling the aging suspension, good tyres, and buying a bit of bling (treat yourself to a carbon hugger or something). If you really want more power from your zxr400, pay a tuner to do the work and ask kindly if he'll talk you through the process of what he is doing, but it will cost due to the time needed.

If you really are determined to know how to tune your engine, I suggest you get down the library and and head to the engineering section and start reading up on engine principles and tuning. There really is no easy answer to this one, but good luck.

MHP should be easy to find as I'm sure they are a little Uk company (someone on here will know). A lot of money to blow on one bit that will do little to improve the power on its own. Just be sure you want to start spending so much money. I'd just by a complete race bike but it would still be a pain on the road (or very good but not last long).

Work on the chassis before increasing power, if you have all that power and can't use it because your suspension and brakes are wrong then you won't be any faster.

Get a decent rear shock, fresh fork fluid/rebuild and set up, then work on the engine from there

StuntRider wrote:where can i get performance camshafts , F3 race CDI , MHP exhaust system , 33mm FCRs, Head work ( what head work should be done) ,SP Cams ,Airbox, Them forged pistions the 57.5mm or 58mm ? & what every other parts are good thanks

there is a set of SP cams on here - see fatspanner#44 but to be honest unless you are planning to race this baby I woldnt bother with any engine work at all - just go with the chassis upgrades

Without doubt this is the most entertaining thread I have ever seen on ZXRworld

Do please keep it going

if u r thinking 1k this mth, 1k next, why dont you consider this?

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