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New Classes for 2006


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Hermit

 
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New Classes for 2006

Sun Nov 06, 2005 10:52 pm » Post: #1 » Download Post

Bemsee/MRO are running this new class next year:

Superbike 400

Any production based machine (ie eligible for a V5) with frame, swing arm and engines cases from the same model, 2-stroke or 4-stroke maximum capacity 415cc.
Minimum weight half-wet 145kg for 4-stroke and 132kg for 2-stroke.
Tyre choice is free.
Maximum bhp 78 (with 2bhp tolerance in exceptional climatic conditions).
How that horsepower is obtained within the above rules is open to each competitor.

The minimum 2T weight seems like it's been set just low enough to allow the NSR to compete. Previously, only officially imported, UK bikes were allowed (Dave Stewart once told me to sell my NSR and buy an Aprilia if i wanted to race a production based two stroke with bemsee/mro!). Seems bemsee have been listening to the riders requests and the new class is the result. The horsepower limit is good for the two strokes too and Dave Stewart points out on the website that that 85bhp FZR won't be able to race in this class unless it is detuned.

I hope someone is inspired enough by this new class to have a go at racing because i'd love to be able to cheer on someone running a Tyga 300 motor. Seeing as Matt made the 300 kit to be an 'all round' improvement in performance i have no doubt he could put together a harder tuned engine that would sit right on the power limit!

You could drop all the standard bike's weight with Tyga bits (gp race seat and subframe, tyga lite ally bits) then bolt a hunk of lead somewhere low down (between engine and expansion chambers??) to lower the centre of gravity but keep in line with the weight limit.

The RGV guys have Leighton Walker in MRO SS400 to cheer on, who's gonna be our man??
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maxim
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Sun Nov 06, 2005 11:23 pm » Post: #2 » Download Post

Hmm.. Sounds amazing. Cool

A fully Tyga'd nsr would be too light though... Mine at half weight, (I presume you mean with all fluids apart from petrol) tips the scales at 124.5Kg... That's weighed on digital vehicle scales with a .25kg tolerance. It's 136Kg fully wet and 119 dry.

But 78bhp would be easy with the 300 kit. Mines at 73 with no engine work.

Those bore strokes are going to get whupped!
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fontyyy

 
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Mon Nov 07, 2005 12:24 pm » Post: #3 » Download Post

A 400 can be "tuned" to spot on 78bhp and 145kg half wet easily, and if they did then get "whupped" at that they'd change the regs again, a capacity limit of around 70% of a 4 stroke is plain common sense, the fact there are no modern 2 strokes over 250cc is the only reason they haven't set a seperate max capacity for them.
Or they could just rejig the "engines cases from the same model" to read "cylinder block(s) from the same model".
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maxim
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Mon Nov 07, 2005 2:05 pm » Post: #4 » Download Post

Still got a soft spot for 400's eh Fontyyy... Wink
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fontyyy

 
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Mon Nov 07, 2005 2:20 pm » Post: #5 » Download Post

Mate, they're good bikes and massively underdeveloped due to 55 bhp jap laws.

Talking to monkey about my slagging of my RVF as soft and slow I said I'd like to ride a proper sorted 400.

How about this? There aren't may (if any) NSR250s or even 300s that could give it a run.

Obviously a 2/ of a similar cylinder capacity will beat a 4/, it has an unfair advantage as it fires every stroke and uses an unmeasured area of the engine (the crankcase and in the case of a modern 2/ the exhaust chamber) to allow it to do so. If engine capacity were measured as volume used by compressed fuel mixture what size is an NSR now?
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Last edited by fontyyy on Mon Nov 07, 2005 4:18 pm; edited 2 times in total
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nsrmonkey

 
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Mon Nov 07, 2005 2:25 pm » Post: #6 » Download Post

maxim wrote:Still got a soft spot for 400's eh Fontyyy... Wink


nothing wrong with 400s Max.
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mat grant

 
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Mon Nov 07, 2005 3:27 pm » Post: #7 » Download Post

What about an NS400 with different cycle parts (ie an RGV)??

Yes it has a V5 and it used to have an MOT...

I'd guess at around 75 - 80 BHP if tuned with 400 barrels.

Maybe it won't get sold for parts....

Mat.
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mat grant

 
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Mon Nov 07, 2005 5:10 pm » Post: #8 » Download Post

Doh!

Just noticed the 'engine cases / frame/swingarm' bit...

Mat.
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Hermit

 
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Mon Nov 07, 2005 6:07 pm » Post: #9 » Download Post

Yeah, so maxim could have his mega light weight 300, then find a way to add weight as low down as possible (hunk of lead bolted under engine??) to bring it back up to the limit (I think WSS 600s have lead bits on them to make it fair for the Ducati scrap they have to race with). Center of gravity will be lowered compared to a stock bike but it will still weigh 132kg!!

With regards to the 400 four strokes, Leighton Walker managed to thrash every last ZXR, FZR and RVF with his RGV250 in one of the races at the last round at Brands and he has finished 2nd overall in the MRO SS400 championship. Leighton said on the RGV forum that his bike is making 60ish bhp. Not 85bhp like that FZR which didn't come second overall...

That fancy 400 fontyyy was on about would finish DEAD LAST with the wrong rider on it, similarly, who's to say if Leighton is all that great (i think he is), a faster guy could perhaps have taken the title on his 250 or a slower one could have gotten lapped at every meeting. The rider makes the biggest difference, particularly at club level, i used to race in the 250MZ class in bemsee and the difference in rider ability is enormous in that championship.

So before they 'rejig' the regs, let's have some NSRs out there!!!!!

YEEAAAAAAAAAAHHHHHHH!!! WOOOOOOOOOOOOO!!!
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maxim
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Mon Nov 07, 2005 6:45 pm » Post: #10 » Download Post

quote:
--------------------------------------------------------------------------------
Originally posted by maxim:
Still got a soft spot for 400's eh Fontyyy...
--------------------------------------------------------------------------------



nothing wrong with 400s Max.


I know! Although I'd only have an RVF... Standard and piped FZR and Gullarm I've ridden were pretty washing machine uninteresting to say the least.

And I'll have a 400/500 twin road racer when they bring them out if they make over 75bhp.

Fontyyy you'll have to do better than an 82bhp Honda mate... Razz I once read an article in MCN years ago about an aussie racer who had built a carbon framed ZXR400 and stuffed a zzr600 lump in it... I think that was about 120Kg...
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rgvsean

 
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Tue Nov 08, 2005 8:23 am » Post: #11 » Download Post

The RGV guys have Leighton Walker in MRO SS400 to cheer on, who's gonna be our man??


I think not anymore. He's going to concentrate on RS250GP now. I believe he has sold his RGV.

The wieght is a problem, a lot of guys have spent a fortune or at least a lot of time with a grinder getting the weight down into the 120's. Although if half wet would be ok I think but VJ21 is lighter still. VJ22 is quite heavy as a stock bike.

There is a new championship based around the old KR cup coming out this year, speak to Mark Jordan for more info as I believe that is going to be very hot at the front.

I still think a really well sorted 250 is better than a 300 due to the gearbox and all the other parts the relavant manufacturer designed around that capacity. Sorry Matt, just didn't enjoy mine but it wasn't a Tyga one so maybe I missed out?

300 probably makes the easier bike to ride.

Also, and rather silly I guess, is 250 just means something. It's a special number, do you know what I mean? Confused Shoot me if you like Laughing [/code]
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Matt@TYGA
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Tue Nov 08, 2005 8:45 am » Post: #12 » Download Post

Hmmm. Interesting.

415cc limit 2 or 4 stroke.......hmmmmm.

78hp? the 300 will hit this and still be rideable. Andy G rode my 300 at about 75hp and said it was boring...fast but boring....some could read that as very easy and tireless to ride.

A 250 will go this figure but it'd be peaky and you'd really have to keep it on the pipe. Miss a gear and those diesels would be off.

A 415cc stroker, especially a twin would be more than a match for those boilers all through the range. You could always fit tiny carbs to kill the top end mojo to 78 ponies. It'd pull off idle like a buffalo on acid!

Hey Fontyyy. That's not fair to say the two stroke's got an 'unfair' advantage because of the way it works. A boiler, if designed correctly, can copy the two stroke way by sucking in extra juice on the inlet thanks to the scavenge effect of the pipe and inertia during valve overlap, and then clever use of tapers in the pipe can plug the charge in the pipe and ram it back in before the valve closes. On top of this, the stroker's got big holes all around the cylinder to deal with, whereas the boiler's all nice and smooth. So who's cheating now?
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maxim
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Tue Nov 08, 2005 8:48 am » Post: #13 » Download Post

Anyway Matt... About that big bore kit we were talking about! Twisted Evil
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maxim
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Tue Nov 08, 2005 8:52 am » Post: #14 » Download Post

There are a few people I've seen with road registered RS's and TZ's... Don't suppose they'd count?! Wink
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Luke F
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Tue Nov 08, 2005 10:23 am » Post: #15 » Download Post

Matt do you rekon you could down size my crf barrel?

mind you my already built 300 racer is in the uk already
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