HP gain?

Ok, my CR250 motor is compeltely rebuilt. Top and bottom end. New Wiseco piston, rings (cylinder in good shape so just honed), new hot rod crank, new seals, completely rebuilt carb, new reeds, new coil, etc, etc, etc.

I also bought a FMF Fatty and FMF Power Core.

So, given stock HP is around 45, what should I expect the power to be on this bike?

Not to sound like a wise ass, but .... 45. However, it might have been a lot less before your rebuild. As the engine wears it drops in power just a little at a time. You don't really notice it from ride to ride.

Maybe a few hp from the pipe.

my guess is 47-48 hp.

47-49

Not to sound like a wise ass, but .... 45. However, it might have been a lot less before your rebuild. As the engine wears it drops in power just a little at a time. You don't really notice it from ride to ride.

Maybe a few hp from the pipe.

Ok so the consensis is roughly 46-49hp. Cool, thanks. I guess I will find out when I fire the thing up :thumbsup:

about 47

The only mod that would allow for more power would be that pipe. But the other stuff just brought it back to "good as new".

about 47

The only mod that would allow for more power would be that pipe. But the other stuff just brought it back to "good as new".

Stock it's 45 hp right? So the both the pipe and the muffler wouldn't add more than a few hp?

Well, you could probaby get a pipe set-up that might ad as much as 4-6hp, but you probably wouldn't care for the powerband! Typically, aftermarket pipes designed for the same bike usage as the stock set-up don't necessaily over big increase in hp, but alter the power band characteristics to suita particular rider's style or usage of the bike. A low-end, grunt pipe may have little effect on peak hp number, but the amount of hp made at different rpm levels. Just picking numbers out of the air here.....say stock was a peak of 45hp at 9000rpm and an aftermarket low rpm pipe was also only 45 hp. No change, eh? Well, at 6000rpm, stock might make 30hp, while the aftermarket might be making 35hp. COnversly, a pipe for a miler might make 49hp at 10000rpm, but at 6000rpm might be only at say 25. With no other mods, most pipes typically move the power band around.

Well, you could probaby get a pipe set-up that might ad as much as 4-6hp, but you probably wouldn't care for the powerband! Typically, aftermarket pipes designed for the same bike usage as the stock set-up don't necessaily over big increase in hp, but alter the power band characteristics to suita particular rider's style or usage of the bike. A low-end, grunt pipe may have little effect on peak hp number, but the amount of hp made at different rpm levels. Just picking numbers out of the air here.....say stock was a peak of 45hp at 9000rpm and an aftermarket low rpm pipe was also only 45 hp. No change, eh? Well, at 6000rpm, stock might make 30hp, while the aftermarket might be making 35hp. COnversly, a pipe for a miler might make 49hp at 10000rpm, but at 6000rpm might be only at say 25. With no other mods, most pipes typically move the power band around.

I've seen a lot of people with the fatty pipes that's why I bought it but I admit I don't know much about what it does to the powerband along with the spark arrestor pipe. :thumbsup:

I your looking for top end HP then you should have got the SST

here are the numbers from FMF

cr250fatty.jpg

02_CR250_DYNO.jpg

Like everyone said - you're just back to stock as far as all the replacements go. The pipe might give you a hp or two at max - but on most CR's I've seen the "Fatty" allowed the bike to rev a lot quicker.

With that said, it's faster from corner to corner and definately more fun to ride if you picked up even a little hp and a little torque. - Mike

My old bike...the one I sold yesterday was a 1997 CR250, it has fresh topend, FMF Fatty, and Boysen rad Valve. To tell you the truth HP #s mean nothing to me. It is all about the power curve. I am 100% sure you will notice a decent difference b/c of the freshened up everything. Pipe should a a little too, so you should be impressed. You have one of the best 250 motors ever made!!!

My old bike...the one I sold yesterday was a 1997 CR250, it has fresh topend, FMF Fatty, and Boysen rad Valve. To tell you the truth HP #s mean nothing to me. It is all about the power curve. I am 100% sure you will notice a decent difference b/c of the freshened up everything. Pipe should a a little too, so you should be impressed. You have one of the best 250 motors ever made!!!

Haha, thanks all. I am sure it's going to be a decent ride :thumbsup: I just have to finish rebuilding the rear suspension and I'm ready to go. Can't wait to fire it up and RIDE!

here are the numbers from FMF

cr250fatty.jpg

02_CR250_DYNO.jpg

Nice handle, by the way :thumbsup:

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