Suzuki GSX-R250R modification?

[The Little Gixxer]

Yes there are definately some things that just shouldn't be done. I didn't really think turboing a 250 was that big an issue or one of those things.

So the gist of the conversation goes:

Yes you can do it but only because you are either an idiot or have very deep pockets. I am neither of these and was looking for some help.

The crux is that either it will be done or not, if I do it then it would be a fun and crazy build wouldn't you agree at least to that?

So I shall leave this thread for a fair while until I have something of more value to say, although I will stick around once the cosmetics are all done to see if at least that part might fit.

I also have something else I could do to it which would raise even more eyebrows but due to the recent reactions I shall keep that to myself until it is built.

Thanks for the comments, the dissing and general put downs.

We shall meet again.......

[SNF]

http://fzr250.com/viewtopic.php?f=22&t=3409

Okay so its a Yam rather than a Suzuki, but it is/was a 250cc ( bored out and a bunch of other custom shit?) Which apparently does an almost 10 second quarter mile. Huge amount of money and work.

Slot in a 400cc motor in it if you really want, that would be easiest to get it to move. There was a 250cc Suzuki on Tm with a 400c impulse motor. That would fly!

Personally I'd do up the fairings, aftermarket exhaust, sticky tires and then just and ride it. Its a 250. Mine is too, I accept it for what it is, I couldn't give a fuck if the 4-600cc guys fly past me, its a road sports bike not a track spec super bike. As long as I'm happy with the end result when it looks sounds and runs good, I'll be happy. That's only what I think though.

If you did make it turbo/did a 400cc swap I'd be impressed, props to you. But really are you sure you want to go to all this effort when you can just get a bigger faster bike?

[blackdog]

[ducatilover]

$5000 - 8000 to turbo that bike. 250's have been turbo'd before with small daihatsu turbos (charade 3 cyl motor) or possibly even a turbo for a honda city (if you can still find one).

IHI RHB31. Smallest common turbo you can find.

It will have to be converted to EFI and run a liquid to air cooling system (or meth injection). All parts will have to be custom fabricated.

No it won't. You can run carbs with a turbo, reliably and flexible, you wouldn't be running north of 6 psi on a 250 screamer anyway as it'd spit the rods even faster.

Turbo on it = very high boost threshold and a fair amount of lag.
You'll need some boss fab skills, oil lines, BOV, external wasegate with a soft spring, boost controller, rising rate fuel pressure reg, low pressure fuel pump (a small Holley one will do), somebody who has access to machines to cut flanges.
You need to run 1-2psi more fuel than boost pressure at all times, hence the RR FPR.
You need to get the length and diameter of the bowl vent tube correct in the air intake, otherwise it'll never be able to be tuned well (fairly easy to do however)
You'll need a bucket for the bottom end when it flies apart.


What I would do (I just got a GSF250 screamer for lulz myself), if the bike isn't a complete shitheap, valve clearances, carb clean/balance, new OEM air filter (they're fucking cheap), new plugs, new leads.
I wouldn't go any further than that, unless you have the audacity to think you know better than a company who can pull 45hp out of a 250? By chucking individual pods on it, you will lose any "bottom end power" it has and gain absolutely nothing up top, why? Because it has CV Mikunis, with flat slides, these rely on still air in the airbox, and the airbox is tuned to a compromise in the frequencies of the intake pulses within certain rev ranges. Unless you reckon you know more than that, leave the wee thing alone.

Spend some time on the brakes/suspension. These are fucking crap on them, so may as well sort them.

Or buy a nicer bike when you can and improve that to suit?

I may have modified a bike once and know how stupid you can get and begin to ruin a once excellent machine.

[ducatilover]

I wouldn't trust a turbo with carbs on a motor that small. Shit will go boom.
OP should really just save for a busa

Find someone who can set it up them, it's perfectly fine.

[98tls]

Wrong forum bro. Bikes of that vintage don't do well when the "mutton dressed as lamb" intent comes along...

Leave out with the "mutton dressed as lamb" eh

[The Reibz]

Looks like its been done.
http://feralinjection.com/cbr/Turbo2.html

[ducatilover]

Looks like its been done.
http://feralinjection.com/cbr/Turbo2.html

Haven't seen that in ages. Has he finished the beast? I reckon you'd get a solid 60whp from a turbo 250/4. Once.
And then it'll still be fuckin slow

[R650R]

This thread has reminded me about the Fast Bikes mag turbo Blade, epic at the time with 185BHP and 185KG but now you can buy that performance of the showroom floor with a warranty and lighter.
If that Suzuki is anything like the others, ditch the end can for something home made to instantly save about 10kg in weight, ditto on the fairings except the front one.

A really good option would be to get on of the old F3 class FZR400 or ZXR400 bikes that had been setup to run on methanol before they banned it. BTW those engines were highly tuned, idled at about 6000rpm and made 75-80hp Methanol is probably cheaper than petrol now, even if the engine uses twice as much.
Put your GSXR stickers and number plate on the outside and you'll be sweet. Side by side its near impossible to tell those 400 from 250 fours.

[Vinz0r]

If you want a fast 250, buy a 2 stroke. If you want to do some fun modding get an NSR and the 300cc conversion kit. That'll keep you busy for awhile and it's possible that you won't blow it up . Turboing your crappy old GSXR is a huuuuge waste of time and money. Everyone has told you this, so perhaps you should take a hint and listen to good advice when it's offered.

[The Little Gixxer]

So does this engine fit the bill for moving to a 400 in the frame?

http://www.trademe.co.nz/motors/moto...-696032775.htm

What if I retune my 250 to run on methanol?

[SMOKEU]

So does this engine fit the bill for moving to a 400 in the frame?

http://www.trademe.co.nz/motors/moto...-696032775.htm

What if I retune my 250 to run on methanol?

No!

That 400cc frame has major gearbox problems as stated in the auction. This alone is a big risk unless you know exactly what's wrong AND how much it's going to cost to fix. You will still have to have the engine fitted to the bike, as well as any electrical wiring that needs doing. I doubt the 400cc engine will bolt straight into the frame without some modifications at least, and then you have to get it certed if you want it to be legal. By the time all that is done properly, it will cost you the entire value of the bike.

Getting your bike converted to methanol is pointless. It's going to cost you a very significant amount of the value of the bike for little gain.

Just ride the fucking bike, and save your money for a better bike instead of all these mods you want to do. You'd be a fool to start spending any more on that bike than you have to, other than servicing and other basic maintenance.

[Mike.Gayner]

So does this engine fit the bill for moving to a 400 in the frame?

http://www.trademe.co.nz/motors/moto...-696032775.htm

What if I retune my 250 to run on methanol?

Please just stop.

[Vinz0r]

So does this engine fit the bill for moving to a 400 in the frame?

http://www.trademe.co.nz/motors/moto...-696032775.htm

What if I retune my 250 to run on methanol?

No longer sure if you're serious. or just taking the piss.

I'm out.

[FJRider]

No!

That 400cc frame has major gearbox problems as stated in the auction. This alone is a big risk unless you know exactly what's wrong AND how much it's going to cost to fix. You will still have to have the engine fitted to the bike, as well as any electrical wiring that needs doing. I doubt the 400cc engine will bolt straight into the frame without some modifications at least, and then you have to get it certed if you want it to be legal. By the time all that is done properly, it will cost you the entire value of the bike.

Getting your bike converted to methanol is pointless. It's going to cost you a very significant amount of the value of the bike for little gain.

Just ride the fucking bike, and save your money for a better bike instead of all these mods you want to do. You'd be a fool to start spending any more on that bike than you have to, other than servicing and other basic maintenance.

Swap a 400 into a 250 frame will be a half hour job at best ... and only an expert on bikes could tell ...

And you'd double the value of the bike ...

Methanol ... way to go ... you can buy it at most gas stations ..

What else could you spend your money on ... booze and chicks ...