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02 hi compression question

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Anything above 13:1 will require race fuel. Even at 13:1 you may get some detonation every now and then

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Do a search and you will find that the agreed upon limit is 13.5:1 on pump gas. Anything higher requires better fuel. I ran a CP 13.5:1 in my 02 on pump gas with no problems what so ever. It never detonated/ran hot. It ran great! The 02 cam is almost exactly the same as a stage 2 cam and loves the 13,5:1 piston. I also ran an 05 flywheel/full 05 ignition, 04 airbox/08 air boot, all used off ebay for lease then $150.00. I also ran a MRD pipe and that 02 was pretty damn fast.

 

The only con is you do not want to install it over a worn bottom end. If the bottom end has 200+ hrs on it then you you rebuild it before raising the compression

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Do a search and you will find that the agreed upon limit is 13.5:1 on pump gas. Anything higher requires better fuel. I ran a CP 13.5:1 in my 02 on pump gas with no problems what so ever. It never detonated/ran hot. It ran great! The 02 cam is almost exactly the same as a stage 2 cam and loves the 13,5:1 piston. I also ran an 05 flywheel/full 05 ignition, 04 airbox/08 air boot, all used off ebay for lease then $150.00. I also ran a MRD pipe and that 02 was pretty damn fast.

The only con is you do not want to install it over a worn bottom end. If the bottom end has 200+ hrs on it then you you rebuild it before raising the compression

Every time I do a top end I check the bottom end for wear. I haven't had this bike long and the highest I really want to go on compression is 12.5:1. But winter is here and it's about time to start tinkering with it and get it ready for summer

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and will I find any power gains from a stage 2 hotcam then? Cause that was another mod I was planning. I'm also ordering a megabomb/q4 exhaust for a little more power. Trying to get as much power as I can without doing a big bore kit. Also have 12/53 sprockets

I don't think so. The 02 cam is the most aggressive cam Honda put in the CRF's. It basically is a stage II cam so don't bother with the Hotcam, you won't see any gain from it.

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I don't think so. The 02 cam is the most aggressive cam Honda put in the CRF's. It basically is a stage II cam so don't bother with the Hotcam, you won't see any gain from it.

Ok so I'm going to go with a 12.5:1 piston replace the cam chain and possibly put a new crank and bearings in. Also with tax money get a fmf powerbomb and q4 exhaust. It already has kibblewhite ss valves. And also going to send the carb to tokyomods.

P.s. Got a guy that supposedly has a 13 yz250f that will run circles around my 450. So just want to get a couple more ponys out of it before I show him what a big boy bike is.

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Ok so I'm going to go with a 12.5:1 piston replace the cam chain and possibly put a new crank and bearings in. Also with tax money get a fmf powerbomb and q4 exhaust. It already has kibblewhite ss valves. And also going to send the carb to tokyomods.

P.s. Got a guy that supposedly has a 13 yz250f that will run circles around my 450. So just want to get a couple more ponys out of it before I show him what a big boy bike is.

that guy must not be very bright nor very good at math.  Its impossible for a 250 to run circles around a 450.

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that guy must not be very bright nor very good at math. Its impossible for a 250 to run circles around a 450.

Now I have had a 07 yz250f that would hang with a stock 06 crf450r. But that yz was built out the ace. Tokyomods head, stroker crank, hi compression piston etc.

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Now I have had a 07 yz250f that would hang with a stock 06 crf450r. But that yz was built out the ace. Tokyomods head, stroker crank, hi compression piston etc.

maybe a yz250 but not a F, no way.  It might keep up with a good rider and a shitty rider on the 450.  But running circles around it will not happen.  I don't care what the names on the tanks are.

you should bet him titles  :ride:

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