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How to modify NSR SP to become a road illegal track only bik


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Behemoth

 
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How to modify NSR SP to become a road illegal track only bik

Thu Apr 22, 2004 2:28 pm » Post: #1 » Download Post

Hi,

I'm new in this forum.

One thing in my mind now is to buy NSR 250 R/SP (MC28) and modify it to become a track only road illegal bike.

Can anyone help me?
Like to derestrict the bike, and increase BHP to nearly 100BHP.
And reducing weight to nearly 100kg, which parts that I need to remove?
Also a gear, air shifter, dry clucth, racing kits, carbon fibre fairing, etc etc.
And is there anything I need to know about this bike please tell me

Okay,
Thanks.
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cgallant
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Thu Apr 22, 2004 3:05 pm » Post: #2 » Download Post

Well in order to get the numbers your talking about, you will need to remove the engine, and replace it with something else. maybe a 600 or something like that.

Honestly, your not going to get 100 HP out of a 250. Just isn't going to happen, no way, no how. Not even with a RS250 engine thrown in there.

Your looking at 75 max on a NSR engine, and you won't like it, as it won't be reliable. Drop an RS250 engine in there, and now you can get 85 if your a good tuner. Still will be doing top ends more often, and doing a crank at least every season, if not more.

Of course if you just start out with an RS250 (Honda that is), then you will already have a bike that will out perform most 600's on the track.
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Behemoth

 
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Fri Apr 23, 2004 2:35 am » Post: #3 » Download Post

Ooo,

Thats hard, I think Aprilia RS250 is much easier to become race spec bike.

But can you tell me how to derestrict MC28 and increase HP to the maximum?
Also which parts thats not important to remove and decrease the weight.

I cannot replace MC28 engine with any other engine because I am entering a production road racing series.

On my mind now is Aprilia RS250 and Honda NSR250.
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cgallant
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Fri Apr 23, 2004 5:56 am » Post: #4 » Download Post

Your not going to get 100 HP out of an Aprilia either!

For information on de-restricting the bike, check out http://www.nsr-world.com/ Look in the tuning section.

As for removing things from the bike? I remove anything that isn't used. If you switch to pre-mix, removed the oil pump, and oil tank. If you don't mind push starting the bike, you can remove the kick starter, and gear, blocking off the hole. Remove the rear passenger pegs, the kick stand, replace the pipes, remove any lighting that is used for street, remove any electical stuff used for street, etc...

it's all standard stuff... you would do this with any other bike.
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Dave Ett
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Fri Apr 23, 2004 8:05 am » Post: #5 » Download Post

Also the radiator expansion tank - you run water only so can top up any overflow.

My MC21 was making 65hp after minor work: Tyga pipes, modded airbox and no filter, HRC jet kit, Tyga stuffers, HRC ignition de-restrictor. Pulled very nicely from 7000 to 11,800 when the jetting was spot on. Other times it'd bog down until 8500 which is why I switched to four stokes in the end - got fed up of rejetting between every race!

You can use RS pistons in the NSR for a bit more power, but they wear out faster. How much money have you got? Wink
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Behemoth

 
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Fri Apr 23, 2004 12:54 pm » Post: #6 » Download Post

cgallant wrote:Your not going to get 100 HP out of an Aprilia either!

For information on de-restricting the bike, check out http://www.nsr-world.com/ Look in the tuning section.

As for removing things from the bike? I remove anything that isn't used. If you switch to pre-mix, removed the oil pump, and oil tank. If you don't mind push starting the bike, you can remove the kick starter, and gear, blocking off the hole. Remove the rear passenger pegs, the kick stand, replace the pipes, remove any lighting that is used for street, remove any electical stuff used for street, etc...

it's all standard stuff... you would do this with any other bike.


I know I cant get 100BHP from Aprilia, I said nearly 100.
And my friend says that Aprilia RS250 can get nearly 90BHP if tuned profesionally.
I join this forum to get an info that I need about NSR250 which is one of my choice for the road racing championship.

And thanks for derestrict and removing parts tips.

Peace.
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Behemoth

 
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Fri Apr 23, 2004 1:05 pm » Post: #7 » Download Post

Since I'm new around here...
So I would like to know how to get the racing parts for MC28. And also about the payment and shipping.

Also I need to know...
What is the most highest race spec NSR250 can achive?
Like HP, torque, weight etc etc.
And I know the brakes must be race spec too.

If I buy MC28, I want it to be a real challenger (or podium finish at least, or champion if possible) in the road racing championship.

Okay, I hope you (anyone who read this) can help me in this NSR info.

Thanks.

Smile
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Dave Ett
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Fri Apr 23, 2004 1:15 pm » Post: #8 » Download Post

Brakes are pretty damn good being designed for the CBR900. Service them and you should have no trouble.

Forks and shock will both need a rework as they'll be several years old and setup for a Japanese waif.

To be honest you're better going with an MC21 as they have a conventional ignition setup, not the HRC card. They also have a twin sided swinger which is lighter than the single from the 28.

However, if you've already got a 28 I guess that'll do!

If you want to convert the thing permanently, then it's worth stripping the wiring loom down so it only has the neccessary bits in it. I have done this on the NC, and it's amazing how much weight you can ditch. This also allows you to site the CDI further forward for crash protection and ditch the charging system.

Don't remove the kick start. It weighs fuggall, and when you stall in the holding area / grid you look a pratt as you try to bump start it.

Ditch the thermostat and tape up the rad if it's running too cold.

Cut the webs from within the airbox to double the capacity.

Use a non O-ring chain, as they sap less power and weigh less.

Saw the back end of the sub frame off as it's doing nothing to support you.

Ditch the rear brake reservoir and just use a longer piece of hose taped to the frame.

That little lot will get you going for the weekend!
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Dave Ett
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Fri Apr 23, 2004 1:17 pm » Post: #9 » Download Post

Oh, forgot to say. Tyga will sell you everything you need and advise you on the best stuff to use for max power. Like the 300cc conversion... Wink

www.tygaperformance.com
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Behemoth

 
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Fri Apr 23, 2004 1:21 pm » Post: #10 » Download Post

Thanks for the info Dave.
May I know Tyga website URL?
Can I make an order online?

300cc conversion? That makes me disqualified in the race.

:D

EDIT: Sorry, I have just noticed your URL there.

Thanks.
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cgallant
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Fri Apr 23, 2004 4:40 pm » Post: #11 » Download Post

Couple more tips...

Anything that is steel that can be replaced with aluminum, do it. Rear sub frame, front fairing/instrument stay, clip ons, etc...

My race bike doesn't have an airbox. It runs wide open carbs, but you need to think about this when jetting.

Also, figure out how much gas your bike will need to run the distance it needs to go, and put just a little more in it. Don't fill your tank to the top if your only running an eight lap spring race. Fluids can add a huge amount of weight to a bike.

Change the rear sprocket from steel, to aluminum.

Chain - Good quality race chain. They are expensive, but they are also mostly designed for bike heavy bikes. They will last much longer on a small 250.

Body work - Get ride of the stock plastic stuff, and go with a light weight fiber glass set. Not to knock TYGA, but their stuff isn't race quality stuff (unless they have changed it in the past year). They built their body work for street use, and it's a little heavier to keep up longer. Get Airtech, or if your in Japan, try Coren. My Coren body work is less the half the weight of my TYGA body work.

Exhaust - Again, get an aftermarket setup. TYGA, Jha, i-Factory, DogFight, etc... anything is better then stock, and the weight savings are HUGE.

Suspension - You don't need to swap it out, but get it rebuilt, resprung, and revalved for racing. This is the first thing I do on any bike I put on the track! I currently have a 2001 Honda RS 250 full front end all ready to bolt onto my MC28. I have put three weekends on the MC28 after it's been setup for me (suspension wise), and I have decided to hold off on the swap. The bike is feeling just fine as it is with the stock suspension.

Brakes - These things are over engineered for the NSR! You dont need to worry about them. Stainless steel lines, bleed them out, put good pads on the bike, and keep the pistons int he calipers clean. They will put the bike on it's nose from 120! Trust me, I came into turn seven last weekend skidding the front tire, with the rear in the air!

Engine - a good porting on the cases, and barrels is only worth more power. It can be expensive to do, and not many know these bikes to do it properly. Find a good place to do the work. A nice light weight flywheel is well worth the money. TYGA has then for sale. Anything that spins that can be lightened get it!

I am sure there is more, but this is getting pretty long. Oh, on the subject of an Aprilia RS getting even close to 100HP. Aint going to happen! That is unless your talking about a factory works bike. People struggle for the same 75 HP on the Aprilia that we struggle for on the NSR. The TZR can be made to do it easly, as the TZR shares parts with the TZ. You can just swap parts in to get more power on that engine. The newer RVG's can be made to go quick, but they crash all the time, so no one really knows if they can finish a race :)

Thanks,
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Behemoth

 
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Sat Apr 24, 2004 12:23 am » Post: #12 » Download Post

Ooo,

I see, I see.
Now I understand about the modification to make for the NSR250.
Okay, thanks CGallant.

Very Happy
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Dave Ett
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Mon Apr 26, 2004 7:35 am » Post: #13 » Download Post

And the 300cc conversion? If you really wanna cheat, it works, as the barrels look the same on the outside. Just don't get caught!
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