Your 250 top speed?

[Dodgy]

but will be able to ride the nuts off it like a 2 smoker

Ah no... No CBR250 will ever feel like a good 250 2 stroke....

[ducatilover]

awesome! that puts it on the lams list of allowed 250s coming up :P
means ill still be able to sell it when im done restoring it to its "as new" condition haha, its been through rough times,
already getting a set of forgies made up for the rebuild, and a wayyyyy better radiator,
wont change anything power wise, but will be able to ride the nuts off it like a 2 smoker

No it won't, because that's power measured at the wheel. The power LAMS will be using is the factory claimed 45hp at the crank (40hp for '93 onwards models)

How much are the pistons costing you?

[16silver]

No it won't, because that's power measured at the wheel. The power LAMS will be using is the factory claimed 45hp at the crank (40hp for '93 onwards models)

How much are the pistons costing you?

got em custom made for 300$ each, (set of 4 including rods etc)
rings were 17$ for a set
was a m8s rates one off before he closes his buisness,
can probably get the build designs if you want tho?

[ducatilover]

I don't need MC22 ones, but I've been looking at prices for my turbo build that's in the planning.
$300 per piston? Not too bad I suppose. Those rings are cheap

Can you put up pics of the pistons/rods? I'm keen to see some tiny forged parts

[yod]

I've been looking at prices for my turbo build that's in the planning.

so you 12 o'clocked your ZZR and that means it's time for a 'turbo build'

[16silver]

yeah ill see if i can borrow a camera,
basically its just 4 SHINY aluminium pistons that has been forged first then machined, looking exactly like that standard ones (with a bit of weight shaved off underneath)
and 4 gold coloured titanium rods in the same shape as the original but wayyyyyy better fitting than the original where the bearing fits in
ill see if i can get ahold of a camera

[bogan]

so you 12 o'clocked your ZZR and that means it's time for a 'turbo build'

Think it was more of a 9 o'clock!

And the turbo build will go nowhere unless there is a camera pointed at him, gotta catch this one on film eh Doug

[ducatilover]

Think it was more of a 9 o'clock!

And the turbo build will go nowhere unless there is a camera pointed at him, gotta catch this one on film eh Doug

I got right 'round the clock lol
I'm not crashing another bike without video evidence of how great I am

so you 12 o'clocked your ZZR and that means it's time for a 'turbo build'

It'll be a wee while away yet, but the plans are all in place for that "one of these days" project.

'Tis logical though.

[Brett]

Lol, SMOKEU obviously doesn't know shite about 4 stroke 250's, I've had my CBR250RR over 180kph several times, on my GPS, with only a couple of mods. Sprockets, jets and needles, a good air intake and exhaust, and that was about it.

In fact, the highest speed I recorded on it was 214kph (GPS again, and yes I do have the recorded 'track' to prove it) when I was running a highly modified set-up, but it wasn't economical for the street so I have since gone back to almost factory settings.

...and the number of times this thread has been resurrected astounds me!

I will call it. BULL SHIT. "Went back to almost factory settings"...bahahahahahahhaa

[Brett]

Lol you can laugh all you want, but when I can keep up with an 1198 Ducati (on a recent ride up to Cape Reinga) and a CB1000R for a fair bit of the way back, who's really laughing?

I am laughing. a 250cc 4 stroke will never hold its own against a 600 let alone a 1000. The only reason you were keeping up was that they must have been riding at or not far above legal road speeds. I have had 5 of the best 250cc 4 strokes available (CBR250rr, ZXR250C) and yes, they are GREAT bikes and lots of fun, but be under no illusions that they would hold feather up to a litre bike.

Really... And in your vast experience you'd know better, huh...?

Come back and talk to me when you've had over 15 years worth of working on engines, fabricating one-off custom parts, modifying suspension, brakes, frames and all forms of electrical componenets, and working on more than a few of New Zealand's best performance vehicles...

In all seriousness then, what had you done to the CBR? My experience with them is that you only get incremental improvements for performance mods.

[Brett]

So your saying if somebody half my weight rode my bike to max speed, the max speed would be the same?

Pretty much, yes. Found this out many times as a 250cc rider. (I weigh 100kg...rode with mates who weighed 60kg...)

[SMOKEU]

In all seriousness then, what had you done to the CBR? My experience with them is that you only get incremental improvements for performance mods.

When I had my MC19 I was a member of CBR250.com and some of those guys spent a lot of money on their bikes including aftermarket exhausts, bigger jets, different carbs ect and none of those mods will make the bike significantly quicker than stock. Certainly not as quick as a good 2 stroke such as an NSR250 or RGV250.

Short of putting a turbo on or tuning it to run on avgas with internal engine mods such as higher compression pistons and extra aggressive cams they won't put out more than 50ish bhp. But then after spending all that money it will be cheaper to buy a mint late model Aprilia RS250 than to fuck around trying to make a 20 year old 250cc bike fast.

[mossy1200]

I had a rg250f once and ran the flying quarter miles at average speed of 178 was off the 180 speedo by a bit but idd say clock would have been approx 20 over true speed.My mates tzr was a few ks quicker.i just dont see how 250 four strokes are doing much over 190 max somehow. 45 hp max at the rear wheel 150kg bike just doesnt add up to me

[The Everlasting]

Well that made me laugh!! This thread looks like it will never die.

Why don't we start a "Your 600 top speed",and a "Your 1000 top Speed" thread...lol. Would make for more interesting reading.

[Brett]

Well that made me laugh!! This thread looks like it will never die.

Why don't we start a "Your 600 top speed",and a "Your 1000 top Speed" thread...lol. Would make for more interesting reading.

Hahaha yeah but there is always something laughable to read on this thread. Someone with a 250 that has hit warp speed.

600 top speed: indicated 276kph
1000 top speed: 180kph
750 top speed: indicated 287kph.