Hi all,

After a few years of racing a 600 then a minitwin, I've taken a sideways step and bought an NC30 to race. Planning on doing a few club races this year & next, then racing it at the Manx in 2016.

The first job was to get it on the dyno & ensure that everything was fine (not that I don't trust the seller, he's a good friend!), more for ensuring I'd not have any problems in the first race!

The first dyno run showed she's a little rich:


So, off with the carbs to see what the settings were:
MJ 126 all round
Needles, the HRC copy ones from RO
35 pilots
Shorter velocity stacks

And a foam air filter in the original housing.

I had a dig through my selection of jets, ended up fitting 120F and 122R mains, on the needles I had some RO NC35 needles so fitted the red topped ones as they seemed the richest out the lot (J9MC I think), but still a lot leaner than the HRC type ones. It's all a guess at the moment, but the next run yielded the following results:


Better, but seemed to be hitting the limiter at 13k, a shame as it hadn't hit peak power yet.

Then tried 118F and 120R and it didn't like it as much


So went back to 120/122 and the needles on the richest setting. Also fitted some 5 hole emulsion tubes front and rear. By now we were running out of time as I was heading off for our first race. Ended up with it like this:


Far from ideal, but it was running and making decent power. That lean-ness at 10-12k looks horrible, would drilling the slides help this?

Anyway, we did well at the weekend, managed a 4th, 3rd then a 2nd in the last race of the day! First outing and came home with a little trophy so all good :)

But the quest is for more power now!

Spec of the bike is pretty good:
Ported RVF motor
Two brothers exhaust system
NC30 carbs
Stock CDI
Stock compression
Quietening gears fitted

I've bought a ram air box to have a play with, am looking at fitting an ignitech CDI. Maybe have the heads skimmed & remove the quietening gears.

Where else can I find a bit more power? Can spend days on the dyno if need be, but at the same time I don't want to sacrifice reliability. I can handle rebuilding the motor at the end of the season, but would rather avoid mid-season explosions!

Old school race bike builder here in NZ came round to see my bits of VFR goodness in the weekend. He said you can take of the ring gears on the camshafts to make a wee bit more power. Thats providing you haven't done so already, apparently it makes the valve train a wee bit noisier but nothing other than that. I will be doing it to my NC30 race project bike I think, this guy knows his stuff and has people from all round NZ sending him engines to build up for racing.

Hello, yes intending on removing the quietening gears!

Have been reading a lot of the forum, seems most of my questions have been answered through searches (who'd have thought it?!).

So will be pressing on in the next few weeks, with the dyno sheets to show the improvements!

What suspension package are you running?
I'm debating what to do with mine, I have to keep the '89 forks to keep it legal for post classic pre '89 class, but I'm open to what rear shock I can run. I'm thinking I'll be putting in a big order to Rick O at some stage later in the year to get it ready for the summer race season

It has a maxton rear shock, and a maxton spring with stock valving. Seemed to work ok at Tonfanau, but will see how it goes at a bigger circuit next month. May well send them off to maxton over the winter.

Finally, for the cheeky part, you're searching for power but have you lost any weight off the bike/yourself? :)

Had to be said...

Good luck next round, hope you smash em!

Funnily enough, since agreeing to buy the bike I've gone from 14st12 to 13st6 in a month and a half.

It's definitely made a difference, I'm feeling fitter & more agile. Just a shame I cannot shrink as 6'4" is not an ideal height for a 400!

The NC is going on a diet too:

False tank with an alloy fuel cell

Carbon ram airbox

Alloy/carbon brackets everywhere instead of the standard steel items

And we are designing a self-supporting carbon fibre seat unit

It all takes time though, but hopefully come next year it will be a bit of a beast & earn us some more trophies!

TyeNoodle wrote:Funnily enough, since agreeing to buy the bike I've gone from 14st12 to 13st6 in a month and a half.

It's definitely made a difference, I'm feeling fitter & more agile. Just a shame I cannot shrink as 6'4" is not an ideal height for a 400!

The NC is going on a diet too:

False tank with an alloy fuel cell

Carbon ram airbox

Alloy/carbon brackets everywhere instead of the standard steel items

And we are designing a self-supporting carbon fibre seat unit

It all takes time though, but hopefully come next year it will be a bit of a beast & earn us some more trophies!

Where you getting the False tank with an alloy fuel cell?

And what brackets are you changing other than the subframes?

A friend of mine has started up a business doing dyno work & fabrication, he's happy to make a few bits and bobs for me if we can sell a few on to help with costs. I'll have a crack at making a fuel cell for it, daresay there will be some trial and error type stuff going on, but it'll come right!

Admittedly there aren't many brackets to replace, barring the clock/fairing mount and the upper fairing stay. Lower fairing brackets too, and battery box.

TyeNoodle wrote:A friend of mine has started up a business doing dyno work & fabrication, he's happy to make a few bits and bobs for me if we can sell a few on to help with costs. I'll have a crack at making a fuel cell for it, daresay there will be some trial and error type stuff going on, but it'll come right!

Admittedly there aren't many brackets to replace, barring the clock/fairing mount and the upper fairing stay. Lower fairing brackets too, and battery box.

I'm on the same lightweight mission. Loyal loss allows me to run a much smaller battery so can be lightweight and relocated.