Ultimate CRF POWER!!

Okay, so here are my thoughts…

The new Honda CRF450R has been said to have around 56bhp, which is slightly misleading… As most people know, it’s not a vehicles true measurement of power, as it’s measured at the crankshaft…

After that power has made it’s way to the transmission it’s lost a fair few ponies…

So I took my brand spanking new bike to the dyno machine (Rolling road.)

To set about finding it’s real power, which was not disappointing at all!!

I found that it’s stock form was around 50 true horses at the wheel!!

Which considering the loss from the bearing drag, rod and crankshaft windage losses, oil film drag, etc was rather good, not to mention the bike was new and I really didn’t want to push it too hard, so I recon it could have easily squezzed a good 2 or 3 more horses out…

So I thought to myself with the low weight and high power of this beast, how could I make it even faster!!

After many hours searching the web I found that the well known company “Yoshimura” work very closely with Honda’s offroad beasts!!

I looked over their products and found that by spending around $5750 would easily pack in 15 Mighty Stallions with their stage 3 engine rebuild and full exhaust system

Taking into account teams racing in Nascar events spend around $100,000.00 for 1 more horse it put a smile on my face!!

And let's just say it'll need a lot more fine tuning!!

And I thought to myself… It’s just not enough, and like flash it hit me, one of the most used power aids!


I read somewhere that just by fitting a turbo kit you can expect to get from between 30 – 60% more power… Well If we can add 60% onto the beast it’ll easily fly past the 100 horses mark…

And all this from a medium sized single cylinder?!?!


Obviously this is all theory, doing such would seriously damage any bike’s reliability!!

And let’s agree that it’s a little ambitious…

Although certain WRC and other rally machines are pumping out between 450-550hp,

that’s just WOW from a 2 litre engine…

So maybe it is possible?

However, with just the 15hp “Yoshimura” can add they do stress Very regular servicing… For example they measure intervals in a number of hours raced.

Wow! 50HP is plenty for me.

It's tough to believe a 15 hp gain from an exhaust system. The exhaust is only half the equation. More air out without more air in can't do much....


15hp with a pipe? i dont think its that much of a gain

50hp is plenty, my 250 dyno 56hp and i can't control that thing lol

Try Decaf next time.

i dont think he was talking about a pipe maby he was talking about a engine rebuild

i dont think he was talking about a pipe maby he was talking about a engine rebuild


My bad, I was a little excited so I didn't explain too well lol...

Yoshimura do some stage 3 engine work plus with their pipe you're looking at around 15HP

It's tough to believe a 15 hp gain from an exhaust system. The exhaust is only half the equation. More air out without more air in can't do much....

It's all on their website...

And as for the air in... I did mention a fitting turbo :moon: I'm sure that'd be enough for the intake for it to work well :thumbsup:

15hp with a pipe? i dont think its that much of a gain

Its not just the pipe. As he said, its all of Yoshi's Stage 3 engine mods and a full yoshi pipe. 15hp may be a hair high but its very close.

Does it come with a blow off valve to scare of slow riders in the corners :thumbsup:

Does it come with a blow off valve to scare of slow riders in the corners :thumbsup:

What's the difference between blow off valve and dump valve or is it just different words for the same thing?

50 hp is a lot of power to move around 400 lbs. on wheels. i have seen 25 hp boats move huge amounts of weight fast on water.

Ask Ron Hamp what he can do for you for $5,750 before sending it to Yoshi.

Ask Ron Hamp what he can do for you for $5,750 before sending it to Yoshi.


Since you have access or money to dyno time....be sure to dyno after you work.

I'll bet it comes back from yoshi with 56-57 at the most, probably more like 55.

for 6000 bucks.....

Turbo would be neat project, but for a dirt bike, if you use it as a dirtbike, it seems a bit impractical.

A guy has a kit out in the wr250 forum that almost doubles the bikes hp he did it on. You can contact him for advise and ideas I bet.

Athena 500 kit, stage 3 cam, kill exhaust, U4, will get ya close to 65 arm wrenching hp, been there done that.

Get a CR 500, put a high comp piston in it, convert it to run on alcohol, and then turbo it. And a 20 shot of nitrous at 85% throttle.

LOL, was at the AMA Superbike round a few years ago and there was a guy running a turbo charged (might have been supercharged, don't quote me) GSXR1000. Real fast on the straight away, but didn't do much the rest of the time. Of course, I think it only made it about 8 laps before the explosion. Believe it was quoted at approx. 2x the power around 300-330 rrhp.

turbos are great for streetbikes and cars but absolutely not for a dirtbike. go on street fire and search for 500hp hayabusa, now thats a turbo charged piece of art. as for blow off versus dump valve although there no such thing as a "dump" valve what u are refering to is a waste gate, and yes the waste gate and blow off valve are 2 different parts of the equation

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