Advice needed on Track NC30

[eamer1989]

Hey All

My Track bike is underway now just a few bits of advice i need to ask you for if that is possible?

Chassis is the NC30 VFR, Im looking to use a 17inch rear wheel on my vfr and im under the beliving if i get a RVF rear wheel or a clone as they call it off ebay it is as simple as a straight swap, i never belive things untill i see it to be honest so i was wondering if that statement is true i would imagine there is some kind of spacer kit would be needed ?

Also i know this would effect the ride height, would i need to just change the link and modify the dog bone as i call it ? Im using a standerd rear shock as i dont have the funds for a nice ohlins.

Im going to need a new chain and sprocket kit for the bike also as i want to get the basic things new to start off with i see there two diffrent types 520 and a 525, whats the diffrence, and is there any diffrence for preformance or not ?

Camshafts is another thing im looking into, i dont want modifed ones but from the standerd vfr engine would it e better to run the rvf shafts in and would i see much of a diffrence ? i belive i could advance timing by a degree also


Are there any modifactions you would recommend or not to recommend? Im seeing alot about fuel pumps and modifactions of making ram air
Where are the kits avaible from and how much for ?

Any Advice or documents would be great if possible,

Thanks Dave

[Riley]

Hi Dave, fist off good luck with your project, the Rvf wheel is a straight swap for the nc30 item although if you are going racing you may want to consider Rick Olivers 750 rear wheel/hub conversion as this gives a better choice of tyres (160/17). Time for a shameless plug I am breaking a very high spec nc30 at the moment and also have a spare 750 wheel in the workshop http://www.400greybike.info/newforum/vi ... 17&t=15142" onclick="window.open(this.href);return false; . Rvf dogbones will compensate for the drop in ride height and an additional 10mm on the shock will improve rake and therefore turn in. Hope this helps, all the best Paul.

[eamer1989]

without the changing hubs to the 750 one, is the problem with the rvf wheel to do with the tyre being to close the to swingarm and couldnt use a 160 tyre ?

no other way to space it ? im lucky to be given a rvf rear wheel which i have to go collect soonish

and thanks riley i will make a proper post on here soonish on the progress and stuff from scratch i took fair few pictures and that so will hopefully be a good thread

[The Hamster]

You can use the RVF wheel no problems at all, it is as simple us undoing the wheel nut, removing the 18 inch wheel and putting the 17 inch one in its place. You don't need any spacers or special adapters for the wheel and there are no issues with it being too close to anything like the swingarm, shock, chain etc etc etc

This will however give you the drop in ride height as previously mentioned which ideally, well, definetly for a race bike you will need to compensate for. This is also done very easily. Leaving your shock alone, providing its setup properly of course, all you need to do is swap the Linkage and Dog Bone (Correct Term!) for the RVF items, which are again a direct swap and this will sort you out! It is good advice however to put an upgraded rear shock in your 'to do' list as it will help immensely.


As for chains and sprockets, I'm not entirely sure the reason why people convert the bikes to run 520 chains instead of 525 standard ones, but i was under the impression it was simply a measure to save weight and rotating mass, and also because the 520 chains are more free and able to take less power away through friction and the like. The downside of the 520 chains of course is that it is weaker and will not last as long, but in general, for racing you will be replacing chains and sprockets more often than you would anyway so this tends not to be an issue. Although this does need to be confirmed!

Im afraid i have no experience or real knowledge with Camshafts or Ignition advancing, although Ignition Advancing is very much heard of in race bikes. Perhaps somebody can enlighten you who has already done it.

Total loss sytems are also common on race bikes, saving a lot of weight and making the engine electronics a bit simpler to use. Again, not much knowledge on this from me, but theres loads of information on these forums if you look for it.


In terms of fuel system, to be honest unless your going for big power (70bhp +), you will be fine just using the fuel tap as opposed to installing any kind of fuel pump. I've only really heard of fuel pumps being on bikes that have highly tuned engines, perhaps with racing profile camshafts and bigger bore pistons and fully tuned carburettors. The standard fuel tap can be converted to gravity feed rather then its usual vacuum fed setup as the old system can easily cause fuel starvation on race bikes. Search for HRC Fuel Tap Mod or the similar for all the information you will need on this.

It is advisable to get a properly tuned race exhaust system and then having the carburettors fully tuned, perhaps to HRC spec where you can get the parts, so that they both match each other and work well together. You will see a big difference if this is done correctly.

As for general advice, choose your tyres wisely. they will make a very very big difference not only to your bikes handling but to the way the bike handles around the tracks. Brakes will need attention too. A lot of people still use standard calipers and master cylinders etc, and then simply upgrade the discs, pads and brake lines to give the brakes much better bite and better feel. I was on a NC30 race bike not so long ago and it had Bendix Race pads all round, EBC Racing Brake discs, but im not entirely sure which ones these were, and it had HEL braided brake lines all round and compared to my standard brakes on my bike, these were just incredible! Highly recommended! Another route of course is to use the CBR600 Calipers and Master Cylinder to give more bite and more compression for the calipers, but to be honest it isnt really necassary, and extra brackets to fit them will only add more weight!


Save weight, anything that can be left off the bike, leave it off! LOL

That will just about do to be honest before you go mega professional with it all..... Just focus on practicing and trying your lines and your lap times will soon come down!

Happy to help!!

The Hamster

[Cammo]

without the changing hubs to the 750 one, is the problem with the rvf wheel to do with the tyre being to close the to swingarm and couldnt use a 160 tyre ?

160 tyres fit fine on the rvf wheel.

[eamer1989]

Thanks for the quick replys all,

Hamster at the moment im running brakes as Blade calipers and braided lines to give it best possible use. Upgraded nissin Cyclinder also

Im glad to hear the 160 tyre will work on the rvf wheel with not having to mod the hub,

What Rear shocks would you consider, ive looked at the RS250 aproch to things and getting it set up to my weight, i mean in genral i only weight 64kg so im kinda light as it is and my shock is solid and feels good what others should i look at as i dont want to spend massive amounts

My front suspension has been set up for my weight and also with ricks kit for adjusting etc

I have a programble CDI to help also
I was only asking about the fuel pump if i were to run Ram air which im considering why im at the build stage

My tyres i already have sorted as i have raced with them in a sv650 class for couple of years and i love the way they are, still fingers crossed i have never done a wet day yet lol

Im looking to weld together a few rear subframes but i wont do this yet untill i look into others designs first because obveruoisly i dont need the rear part of the frame as i have no pillon but i was thinking of moving the basttery, total loss systems i was thinking about but my only problem is wouldnt i need t osomething in place of the generator ?

Does anyone here who is willing to help on advice to Ram air etc and what kits are around

Thanks Dave

[eamer1989]

Also i forgot to mention i have a ethos system donated to me from a rather nice guy lol

[Cammo]

Does anyone here who is willing to help on advice to Ram air etc and what kits are around

I think for ramair it's best to spend on a sorted setup from the likes of BMC or Chris' (Dynopro) setup. If you fit ramair there are some plumbing mods you need to do to the carbs, it's not as simple as fitting a new airbox.

Improved rear shock is difficult on a budget. Any aftermarket shock will easily be better than the standard nc30 unit. However the nc shock will perform better (if it's in good nick!) if you redrill the linkage to make up for the loss of ride height with a 17" wheel. When you shorten the link it changes the shock ratio which makes it firmer, a good start if you're on a budget.

Peeps have used gsxr k series shocks with some success (which are cheap used), but you might need to relocate the battery because of the piggyback res. Not so much of a problem if you use a very small battery (ytx4 etc - wiring extensions needed).

[eamer1989]

Rite so im going to cut loss's and find myself a Maxton rear shock when i get my redudancy money together, what type do you think i should go for, i mean theres a Sport shock from rick costing 350 or a track with rear res for 450, i mean the shock is built for your weight i presume so what do you guys think

I Tested the engine out today and got the carbs running sweet i do have one of those HRC Trays to direct air better or something got given for free etc. Do you think its worth it and also is it hassle to do so.

I was looking of a website and the bracket for the carbs they say modify it but holes in side etc and changing the stacks to short ones, any idea where i can purchase a set from ?

thanks Dave

PS. i will start a new post very soon with all the build riten up and pics

[Cammo]

I was looking of a website and the bracket for the carbs they say modify it but holes in side etc and changing the stacks to short ones, any idea where i can purchase a set from ?

This is the hrc nc30 carb setup. Details below:

http://www.akhara.com/nc30/nc30hrccarb/index.html" onclick="window.open(this.href);return false;

The air tray is made to work with the hrc carb setup, it ducts air into the carb area. Not much of a benefit if you use an airbox (my opinion only!).

I have this setup on my racebike and it works very well. You need all of the parts for it to work well. Velocity stacks, needles, emulsion tubes, slides, jets etc.

Original parts are difficult to find (stacks are rare now) but there are replica parts you can use you but you'll need to do some mods to the carbs to get everything working well.