new zxr 400 l5

[andy r]

hi I have just got my first zxr400 and i did a track day at cadwell on wednesday, the bike is very good and i had a great day the only thing is i could do with a bit more power, i was just wondering apart from exhaust air filter and dyno is there thing else that i can do which dose not cost a packet ? i have been told that the fly wheel can be machined down but i have no more info on that. any help would be wecome cheers andy

[Davw]

It only really makes sense to spend money on boosting the zxr400 power if you are racing other 400's. If you are only using it for trackdays then inevitably (regardless of how much spending) you will be blown away by the bigger bikes - although not in the corners where the real fun with the zxr is to be had.

Cost to boost 400 power from a standard 62 -64 bhp to say 72- 74bhp will be:-

Exhaust = £200 (this gets a second hand micron system - maybe)
Ram air - not really practical unless you modify radiator etc = £200 (ram air box/ snorkel - then a load of time fitting it)
Carb upgrade (bigger main jets and bellmouths) = £80
Engine work (porting, cams, skim head) = varies but at least £500 (probably more)

This assumes you do all the work except the top end rebuild - so £1000 will get you to 70ish BHP - but you will still be blown away on the straights by the 600's. It is possible to get up to around 80BHP but that takes disproportionaly more cash on ignition, more engine work blah blah blah. I started with a £750 road bike and have spent at least 3 times that (and counting) to get into race trim (add to the above the suspension upgrades, brake upgrades, fairings etc etc) . (total cost so far = £3000 - at least)

If I was only doing track days I would have used the zxr400 to develop track skill and then sell/ upgrade to a 600 - or bigger.
I have just bought a mint FZR1000 (£600) specifically for trackdays.