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2014 Honda CRf 450 in need of low end power

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I recently purchased a 2014 CRf 450 . I own a 2008 CRf 450 also and thought the new bike would be a great upgrade . It lacks low end power compared to what I am used to . I have installed a yoshimura exhaust , yoshimura pim 2 , and a 13:5-1 piston . The motor makes great power on the top end . Is porting the head the answer to get more grunt on the bottom ?

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Well, by putting on Yoshimira products you have guaranteed less bottom end: the yosh products are mid to top end power increases, and a high compression piston takes away from the lowest rpm torque.

 

Yosh and Hi comp will push the power and torque curve up for a more explosive acceleration, for jumpy - track work.

 

Dubach Racing exhaust is what you want for a broad powerband, along with stock compression piston for lowest rpm torque.

 

The '08 has a bit more reciprocating mass on the crank, so if you want less stalling, a small Flywheel weight will help that. It won't actually increase measurable torque, but it will feel like it did.

 

The PIM 2 will allow you to adjust fuel for rpm and throttle postion, so you can mimick the '08's adaptive ignition curves in first and second gear.

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To add low-rpm torque you need to add low-rpm cylinder pressure. You do that with a high-compression piston and/or a camshaft change. Head porting won't help the low end as much as it helps the mid-top.

Ron Hamp has the camshaft you need and the 13.5 pistons, as well.

Edited by Eddie8v

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Interesting. By just adding a Yosh system & remap on a 10 there were some noticeable gains in the lowend & thru the rpm range.  I'd think with the 13.5 HC piston it would get you some extra HP/ torque thru out the powerband.  

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The only thing that makes sense to me is your 08 has a stage one cam and that's what your used to.

Nobody ever says the newer models have GREAT top end. And with a 13.5 piston you should def have enough low end. You can sacrifice some top end put a stage one cam in it, megabomb header and remap for a big bottom end difference and switch the gears up a little to get some top end back later if you want.

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Need to remap the PIM it's is not adding the needed fuel for the cam and compression. The stock MAP is for a exhaust system only. No doubt power is being given up there. You would t modify a carbureted model without carb jetting and expect proper gains. Beyond that get a setup from Ron Hamp he can get you I to the 60+ HP range.

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Once you ensure your fueling is in the ballpark, start looking at 1-2 degrees of ignition timing advance on the ECU along with a 2-3% increase in fueling in those areas, that will raise cylinder pressure and help with low end a bit. Especially if your bike has the beginner/mud map flashed, which is actually retarded 1-2 degrees on the bottom/mid.

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Have you tried going up 1 tooth on the rear sprocket? The may give you what you want for $60.

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Would run a stage 1 hot cam and drop a tooth in the rear. Remember that small changes in gearing will make a huge difference in the way the power is sent to the rear tire. With that said you will lose top end by going down on the sprocket /s

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When I switched from my 08 to a 09 fuel injected CRF450 I found it to be slow, but purely bottom rpm's it pulled stronger compared to my 08.

Euro bikes are in desperate need of an aftermarket exhaust (Akrapovic on my 14) but otherwise in stock I think this bike is pretty fast. (former national licence holder)

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