FXR150 engine modifications?

[hmurphy]

I have searched the forums and haven't found what I wanted. I might be able to but it would take a lot of reading.

Basically... how do I get more performance out of my FXR150 engine? It is now a 156cc engine with hot cams and I am running it on avgas (because a couple others told me I should). The bike is faster than it was when it was stock but not by a massive amount really.

So... what have other people done from here? Raise compression etc? I don't know how it all works with the FXR engines and I don't know how much it will cost. I don't want another 10hp, but another 3 - 5 wouldn't hurt.

Cheers

[Moooools]

Waah waah waah my bike's not fast enough.

You could try to port it yourself and fit a high compression piston.
Or send it to someone along with a big pile of cash. Maybe your friend Gavin?

I'm sure someone will be along with some more useful and specific advice.

[koba]

I have searched the forums and haven't found what I wanted. I might be able to but it would take a lot of reading.

Basically... how do I get more performance out of my FXR150 engine? It is now a 156cc engine with hot cams and I am running it on avgas (because a couple others told me I should). The bike is faster than it was when it was stock but not by a massive amount really.

So... what have other people done from here? Raise compression etc? I don't know how it all works with the FXR engines and I don't know how much it will cost. I don't want another 10hp, but another 3 - 5 wouldn't hurt.

Cheers

Break into Rich's garage with it and do the old switcheroo with his last one?

[hmurphy]

Fucken genius Malcolm.

[richban]

The more air / fuel getting pumped through the more power. Little bit of porting, bigger valves, not to much compression don't want to loose top end. There you have it. More power. Oh and get the fueling and exhaust right. Go to it.

[hmurphy]

Awesome. Where/who do I go to for that stuff? Any decent places or people in town?

[Shorty_925]

Should add 40kgs to yourself and run a stock motor

[F5 Dave]

Waah waah waah my bike's not fast enough.
. . . .

That's gold.

Actually in the Richban vids Gavin's bike did seem quite quick.

Just use the Fishie approach. Open the throttle & don't close it till its too late & make it anyway. repeat.

[F5 Dave]

Should add 40kgs to yourself and run a stock motor

I could retort with 'make it 15 & run an engine 1/3rd the size of everyone else'.

[Buddha#81:Me]

chase as much hp as you like it wont make up for riding skill. There are a couple of young guns down here on fairly standard FXR's that constantly give us the learn.....unfortunatly one seems to think he wasnt fast enough so has gone to a CBR!

[hmurphy]

So you're saying I don't have enough riding skill?

That may be the case but I still think another 5hp might be nice. I personally think it's pretty obvious that I'm losing a fair chunk on some of the straights to the likes of Gavin's, Richard's and Andrew's bikes. I can also see where I need to improve by watching the videos, and places where I make a bit of ground, but I'm still riding below a 43 sec lap on Kaitoke and that keeps me happy.

[Buddha#81:Me]

So you're saying I don't have enough riding skill?

Might be.....but that would be rude when i dont even know ya.......Fishman seems to go ok with a poxy Luncheon. Maybe look at handling first?

[richban]

Funny shit. Well this is motor racing and it is most certainly not an even playing field.

Asking how to make your bike go faster from your option is a little dodgy. You can't really believe anything I tell you for one.

[F5 Dave]

Might be.....but that would be rude when i dont even know ya.......Fishman seems to go ok with a poxy Luncheon. Maybe look at handling first?

yeah he did that & copied Fishies setup.

Have a look at Richbans vids, the first one. You will see Hamish pop through several times making up for Rich's Millenium Falcon riding like an Injun hiding behind the horse (actually shown well in Avatar) Unique style, but can't argue with it working.

[Ivan]

if you havent done anything allready get the suspension set up properly you can chase all the power in the world but if the settings dont allow it to handle nice its a waste, get as much weight off the frame to that will make a differnce

bigger carb jetted properly with the ports done would give you abit even if its just cleaning the ports up and taking out any impuritys in them quite a few guys i know who built hot rod dirtbike engines reckon dont polish the inlet port leave it rough as the fuel and air mix better some guys say polish it tho i guess it comes down to what looks better on a dyno.

exhaust system if you havent done it,

another option to the compression raise is look at getting a copper headgasket made half the thickness of your standered one good thing with copper is you can glow it red and cool it down and reuse it again to, was something i got taught when i was working for a mechanic