06 CRF450R. What crank/piston for high RPM extra power

Ok, so I have a 06 that is all stock as far as the engine is concerned.  Stock exhaust, all OEM enigne parts (not origianal but OEM).  Well I have about 160hrs on it and just noticed a ticking noise.  Pulled the filter and see copper flakes, so I'm sure my crank is on its way out.  It was still running just fine, but I'm sure the crank is tired as well as the piston (82hrs). 

 

What I plan to do is a new crank, piston, main bearings, and cam chain.  Question is what piston and crank to go with.  OEM is generally good but since I'm digging in (can do all the work myself) I figure now might be the time to bump up the power a bit.  My rules to pay by are:

 

1. Keep the $ reasonable.  No exotic kits that are just silly expensive.  Probably keep the stock stroke.

2. I'm 37 and pretty quick.  Used to ride lots of MX but not so much anymore.  The hardest thing I do to this bike is 2hr endurance ice racing.  This is pretty much straight torture on the enigne.  Lots of time at WOT, dancing through the gears, and lots of RPM.   

 

So, which crank can hold up to this type of duty cycle?  OEM, Wiseco, Hot Rods, Other???

Also, which piston, and what compression.  I had great luck w/ OEM, but if I can bump my compression a bit and get more power and still have an engine that will live I'm in.  Also, there will be no porting, cams, or exhaust mods as $$ will not allow that type of investment right now.

 

Thanks in advance for any tips!

Hot rods cranks,stock stroke. 13,5 cp piston kit(best quality in my opinion but use whatever company you want) also Manuel cam chain tensioner along with new chain... Then you should be all good!

have a Carrillo rod installed on your webs and weld the pin. a 13:5.1 piston (I have a JE for sale), valve job, new springs (make sure the exhaust guides are good), maybe TRX exhaust valves, cam chain, bearings, and seals.

have a Carrillo rod installed on your webs and weld the pin. a 13:5.1 piston (I have a JE for sale), valve job, new springs (make sure the exhaust guides are good), maybe TRX exhaust valves, cam chain, bearings, and seals.

 

What to do  ^^

but id not do trx valves.

What to do  ^^

but id not do trx valves.

Why not the big stems?

Why not the big stems?

 

big stems sound good for making the heavily side loaded valve guides live.

but are they not also stainless steel?

Heavy is bad, light is good. Go all-titanium, baby...

I have ti in mine but I also have my head ported and a stage two cam. If you want more power up top they say you can get two hp's out of ti valves. If you run a stock or stage one and want the valves to last longer SS is your best bet IMO

Mines also a 06 btw also I'm gonna add mine really rocks but I love having the fastest bike but it is a workout and does wear me out faster than a stock bike. It's all in what you want out of your bike

Edited by Diggla117

Bigborethumpers.com has everything you need. New crank with Carrillo rod on it for $539.95. CP pistons Finished blocks. Finished heads on the shelf. Ported heads in a few days of the order.

A properly modified motor with more tq and hp is easier to ride than a modded motor with a Stage 2 camshaft. That big lift/duration cam pushes all the usable power too high into the rpm range and makes the bike abrupt and hard to ride. You want a smooth flow of high tq in a linear fashion from way down low through the rev limiter. You need a ported head, HC piston and a fairly non-aggressive camshaft, even the stock cam is almost too aggressive.

The head was was gone through last year by Millenium Technologies.  Just has the stock TI intakes and stock stainless exhaust valves.

 

Question on the 13.5 pistons.  Obviously the increased compression will give more roll on toruqe, but does it help, hinder, or feel any different at high RPM?  The bike runs fast right now, just looking for a little something extra since I'm rebuilding.

 

Also, I know this has been in about 1.2 million threads, but at what compression point will I need race gas?  Remember, this will be run hard on 0degF days when the air is nice and dense.

 

Again, thanks for the replies!!

A properly modified motor with more tq and hp is easier to ride than a modded motor with a Stage 2 camshaft. That big lift/duration cam pushes all the usable power too high into the rpm range and makes the bike abrupt and hard to ride. You want a smooth flow of high tq in a linear fashion from way down low through the rev limiter. You need a ported head, HC piston and a fairly non-aggressive camshaft, even the stock cam is almost too aggressive.

I'm open for suggestions sir. I thought about calling Ron. Since I talked to dean at r&d and finally got my carb about tuned in she's been a real handfull. I'm pretty impressed with all the work I done and wouldn't be surprised is it was sitting damn near 60hp's. Also the head was ported for the stage two so.. I have to find a cam to go along with the port.

Sorry OP I know you could careless about another cam.

I only work on FI bikes so I'm not too familiar with the older bikes, but I would say 160 hrs of high speed, high rev, WOT,  use is outstanding.

 

Whatever you were using I'd use the same thing over again. 

I only work on FI bikes so I'm not too familiar with the older bikes, but I would say 160 hrs of high speed, high rev, WOT,  use is outstanding.

 

Whatever you were using I'd use the same thing over again. 

Yeah, that is kinda my thought.  If anyone is interested, this bike has been lubed its whole life with Yamalube semi-synthetic 10w-40 in summer, and 0w-? in winter.  Asside from the crank issue, the insides still look new, and shifting is amazing.

Chances are the exhaust guides will need replaced, but maybe not.  You can rebuild your crank with a good rod for the price of a new oem crank. A little more compression will give it a harder hit. I run my '08 stock on the ice and it's plenty fast. You don't need race fuel with a 13:5 piston, but you better jet it for the cold. Probably don't have to tell you that.

rebuild stock crank with prox, cp je or oem rod use kenoconnorracing.com

 

13.5 piston of any brand.

Hot cams stage 3

 

whent he head wears out, 599$ rebuild from fastheads.com  you send them ur head they rebuild it, new ti valves, copper valve seats, new exhuast guides. Last forever but still revvs to the moon.

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