08 crf450 hard to kick

Racer_Twentynine
Edited Date/Time 3/6/2014 12:16pm
As title says I have an 08 that is a real pain to kick over.
I got the bike who got it from a guy who got it from another guy etc........lol
Basically traded a cbr600 I had for it plus cash using a middleman at work.
The middleman has a friend who worked as a factory mechanic who checked the bike over and made a few adjustments
The story I got was.
The bike has a real high compression piston in it and that's why it's so hard to kick over.
At first I was ok with that as the joke was every time someone asked to ride it I said sure if you can start it. Nobody has been able to.
So now I'm at the point where I'm really sick of having a bike that is so damn hard to kick and I'm starting to wonder if it is something else and the high comp piston is just a bs story.

Also bike runs strong as hell once started but if I have a tip over I'm off the track for 10 min minimum.

Any insight???
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slipdog
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slipdog 9/18/2013 4:52pm
9/18/2013 4:52pm Edited Date/Time 9/18/2013 4:54pm
It's not the piston, stock is 12.5:1 and I have a 13.5:1 in my '08 and it starts easy every time.

Do you mean you have to kick it many times to get it to start? That could mean a valve clearance issue.
mynewcr250
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mynewcr250 9/18/2013 5:03pm
9/18/2013 5:03pm Edited Date/Time 9/18/2013 5:08pm
I'm not familiar with 4 stroke bikes but I've ridden a stock 06 and a stock 07 crf450. One was just like yours, super hard to kick over and also harder to start. The 06 however kicks easier than my 250sx 2 stroke and starts in 2-3 kicks from cold.
Paw Paw 271
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Paw Paw 271 9/18/2013 5:06pm
9/18/2013 5:06pm Edited Date/Time 9/18/2013 5:08pm
The auto decompression device may be faulty. It is on the end of the cam shaft and actually lifts a valve off it's seat to allow for easy starting. It then is released when the engine starts running. Your year had a new device on it as compaired to earlier years. The older units had an adjustable arm that pushed down on an exhaust valve and if not adjusted correctly it would also be very hard to start. The one like you should have in the '08 does wear out over time and is not adjustable. It is also possible that it has been removed or has broken. yours should look like this in the link. http://www.bikebandit.com/houseofmotorcycles/2008-honda-crf450r/o/m1749…
coastie44
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coastie44 9/18/2013 10:20pm
9/18/2013 10:20pm
Or it could simply be off a tooth on the timing. Pretty easy to do that when shimming or changing out a cam or piston. not hard to check either. And bike will run just fine.

Don't ask me how I know. Smile

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Beast666
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Beast666 9/24/2013 6:30am
9/24/2013 6:30am
Check your ex valve clearance and decompressor operation with the head cover off the bike and turning the motor over by hand. If the valves are loose the valve will not open up enough to blow some compression off. Also you should hear a distinct "Click" when the ex valves close after comming off the decompressor pin on the ex lobe of the cam. You should be able to see the ex valves open slightly when on the decompressor pin.
Racer_Twentynine 2/16/2014 5:39pm
2/16/2014 5:39pm Edited Date/Time 2/16/2014 6:07pm
ok been toughing it out but time to get this thing fixed. cracked the valve cover open tonight and it does appear that the timing is off. but another question. i was looking at pics at this link

http://www.thumpertalk.com/topic/781210-timing-your-crf450r/

looks like who ever set it last used the wrong mark the mark on the left or the second mark on the fly wheel.

now when i do go to adjust timing do i need take the tension off the chain and do i need to remove the decomp shaft?
Racer_Twentynine 2/17/2014 6:14pm
2/17/2014 6:14pm
Ok not to answer my self but to follow up for anyone searching and looking for answers in the future.

Yes the hard kick as in it took all of my weight and strength to get the kick start lever down was because timing was off.

The timing marks are kinda touchy to line up but once you have it right you can tell a difference.

Use the kick lever for large movements. For small movements you can grab the cam wheel with your hands and get it to move the little bit you need.

Yes release the chain tension. You tube it all you need is a small flat tip.

Cam bolts are Allen head and tight use a quality allen wrench and be smart about holding the cam. Dont go gouging parts in the motor.

Put the tension back on the chain

Dont forget to hook ip the plug wire. You will kick and kick then get paranoid you messed something up. Again don't forget to hook up plug wire.

Now put on a running shoe and and feel the ease of a properly timed kick lol. I have had the kick lever come through the sole of my mx boot so to be able to kick with a running shoe on was sweet.
CarlinoJoeVideo
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CarlinoJoeVideo 2/17/2014 9:20pm
2/17/2014 9:20pm
I would say check the auto decompress lever. Or does it have a hot start lever near the clutch perch? Have you tried that?
Paw Paw 271
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Paw Paw 271 2/19/2014 12:43pm
2/19/2014 12:43pm
If it's hard to get the timing marks to line up perfectly, you have a worn cam chain and it needs to be replaced.
Missing_Muffs 2/19/2014 12:49pm
2/19/2014 12:49pm
Paw Paw 271 wrote:
If it's hard to get the timing marks to line up perfectly, you have a worn cam chain and it needs to be replaced.
thanks will look into that. for now i am just happy i can kick the thing and not look like im trying to hump it.

also happy to see that the scary 4 stroke top end isnt as scary as it seems. I know hteres a ton more to it but i also checked the valves while in it and all was good.
Paw Paw 271
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Paw Paw 271 2/19/2014 5:41pm
2/19/2014 5:41pm
Paw Paw 271 wrote:
If it's hard to get the timing marks to line up perfectly, you have a worn cam chain and it needs to be replaced.
Missing_Muffs wrote:
thanks will look into that. for now i am just happy i can kick the thing and not look like im trying to hump it. also...
thanks will look into that. for now i am just happy i can kick the thing and not look like im trying to hump it.

also happy to see that the scary 4 stroke top end isnt as scary as it seems. I know hteres a ton more to it but i also checked the valves while in it and all was good.
If you let the cam chain go too far in wear, you will find out what it's like to put a 4 stroke jig saw puzzle together. Don't wait, replace the cam chain to be sure.

Paw Paw
Racer_Twentynine 2/20/2014 6:51pm
2/20/2014 6:51pm
noted.
thanks for the heads up. will look into that and a top end while im at it. called a shop for a quote today and gonna be doing this one myself.
mark_swart
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mark_swart 3/4/2014 6:18pm
3/4/2014 6:18pm
Racer29 - You've already done most of the hard parts (dealing with timing), the piston replacement isn't too tricky. Pick up a competition manual (you can find .pdf ones for free on the web) and just follow the steps, double check, and take your time.
I picked up an OEM top end kit for my 06 for $150 on ebay.
mark_swart
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mark_swart 3/4/2014 6:18pm
3/4/2014 6:18pm
Maybe I should have said "intimidating" parts instead of "hard" parts.
Missing_Muffs 3/6/2014 5:51am
3/6/2014 5:51am
mark_swart wrote:
Racer29 - You've already done most of the hard parts (dealing with timing), the piston replacement isn't too tricky. Pick up a competition manual (you can...
Racer29 - You've already done most of the hard parts (dealing with timing), the piston replacement isn't too tricky. Pick up a competition manual (you can find .pdf ones for free on the web) and just follow the steps, double check, and take your time.
I picked up an OEM top end kit for my 06 for $150 on ebay.
yeah the scary part was pulling the valve cover once inside it all looked pretty standard gear head type stuff. had a pucker moment when i took it for a test ride around the neighbor hood and noticed oil all over the place. the valve cover bolt at the rear wouldnt torqe down. pulled it appart again and a helicoil came out all mangled up.

luckily the threads were in the cam carrier and not the head. i was able to re-tap the treads and put in a new helicoil and all is good. who ever hacked it up last time only went deep enough to sink the heli coil. this time i ran it a bit deeper for a tighter fit.

the bolt hole went all the way through so i was able to catch all the shavings from the tap. spent a little extra time to make sure i got it all.

top end will come soon. will have to tear it down and measure before i order parts though. the bike has a AMA tech sticker on the frame so its been through a lot. no telling if its standard bore or not.

and yes
Missing muffs and Racer_twentynine are both me. at work i use the missing muffs and home my son is logged into everything and Racer_twentynine is him. im to lazy to log him out and log myself in.
mark_swart
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mark_swart 3/6/2014 12:16pm
3/6/2014 12:16pm
If it's AMA I like to believe it should be stock bore, but yeah, who knows. Can't hurt to measure I guess. Good luck!

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