Hey,

Just started some track work and really need to adress my suspension issues and was hoping someone will know some answers, i have a 91' MC21 w/ SP front&rear

my problem is the front is way to soft, and has no dampening, well no where near enough, so looking at 15w oil to increase dampening but also need springs. Is there anything that will work from another model, bigger bike with same spring sizes? or where can i find new ones ? Ohlins, aftermarket etc?

As for the rear, i need it higher, what are my options ?

Thanks in advance,
damo

Race Tech (http://www.race-tech.com) makes valve kits, as well as can source springs for front and rear on the NSR.

Not sure, but you can also try Traxxion Dynamics (http://www.traxxion.com/) to see if they have an AK-20 kit that will work on the NSR. THey can also source shock springs for you.


For the ride height, you are stuck to the point where there is no true ride height adjustment on the stock shock. The HRC shock has it, but you will need to find one. Ohlins can make you a rear shock (just need to convince them they can for the most part) with proper ride height adjustment.
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Charles Gallant

Ohlins makes a rear shock for the mc21. Here is a link. Also what Charles said race tech has front springs and valves. You can also fit a CBR 6000F3 rear shock.
http://www.ohlins.com/Motorcycle/Hidden/Recommendationlist/tabid/110/Default.aspx
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Cheers for the quick reply's

The fork springs i can find prices on, not quite the MC21 but ill email them about that, probably just my searching skills need some work.

As for the Ohlins rear, looks sweet, but what do they normally cost?

On the cheaper side maybe, what year CBR600F3 shock, does it have the comp/rebound adjustments? close enough spring rate? but just longer body?

damo.

A lot, I was quoted about £450 (uk, thats $900 US or about $1000 aus) by K-Tech, obviously not very practical for you as they're UK based but the info is still valid, they know their stuff and do the suspension for about 1/2 the British Superbike grid.

I told them I just started racing it, so wasn't exactly a front runner but even to me the bike was more than a bit skittish under braking and they advised one of their 20mm piston kits could be fitted and they could respring it to suit me. They said they'd not done an NSR250 before but that it'd just be a normal Showa Honda fork and asked me what the bike weighed and what I weighed kitted up. Reckoned they could "transform the handling".

Then they said (about the rear) the Showa (remote res) unit is basically very good but lacks adjustability, he said they could refresh and rebuild it (it had a leak) for about £70 or supply an Ohlins one at the price I mentioned above but said "it's not cheap, how fast are you? That stock shock can win club races easily". Regarding fitting shocks from CBR600's and the like they said dont just fit a shock from a bigger bike as race bikes don't have hard suspension, they have effective suspension, it's not the same thing.

So that's what I had done, the bill was a tad over £500 and I've not twiddled anything, just bolted it on, they reckoned it would be close to spot on as they set it. Made a massive difference under braking, in corners it just goes where you look and even with the engine getting tired now (53 bhp on the dyno the week before last, that's 10+bhp down on most of the grid, maybe 20 or more down on the fast 400's) I was able to get on the pace of the back of the "chase pack" and lapped a couple of seconds a lap quicker (round a 60 second lap) than guys I struggled to beat last year.

I was going to ask one of these trackday suspension experts to help set it up and when it does something other than exactly what I ask I might do.
Until then it's better, far far better than me
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