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Cam chain tensioner

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So getting ready to tear down the 450 for overhaul/upgrade. Pretty well got all my stuff. 

This is my 4th 450R, had a 250R and my daughter has a 150R and I've never have had even a loose cam chain before.

My question, while I've heard a couple horror stories on failed tensioners, how may of you have actually had a failure?

 

 

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not me but I didn't want to either so I went MCCT.  Water pump failed just like a lot of other people here so why chance the engine for a cheap fix.

Edited by ramjetV8
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I had a catastrophic engine failure on my 03 CRF450R. Wide open pull up a large sand hill when it let go. Resultant damage... 2 broken intake valves, piston jammed vertically in bore, bent connecting rod.

 

Replaced:

Head

Valve train

Connecting rod

Cylinder

Piston

Camshaft

Cam chain

radiator (long story, read below)

ect...

 

The worst part for me though, was the fact we were a good two hours of single track trail away from the truck. Had to ride double to get back to the truck, and the next day brought a grizzly 4 wheeler and laid the bike on the back rack while I rode on the front rack to even the weight. We tipped and rolled the poor grizzly three times because of the single track trails. Bike suffered crushed radiator and broken plastics. And it took about 8 hours to retrieve.

 

Now, I know there were some problems with the 02-03 era tensioner but after that experience every bike I have owned since got a MCCT.  My 04, 05, 07, 09 CRF's all got a MCCT within 1-2 rides of purchasing them. Take everything with a grain of salt though, considering the population of bikes the failure rate is pretty low. Chances are, you will never have a problem, but for me personally I will always have a mechanical one.

 

Regards

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I have herd of OEM tensioners failing new. It happens. If you think about it take a spring and smash it down for say a year in nearly that same place and hit it with heat cycles. At some point it will stay that way do to the memory of steel. Even spring steel. Manual cam chain tensioners are the way to go. 

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I'll bite:

most stock 450s get along very well with the stock tensioner as long as the bike is not being used for flat track or high speed use and shut very quickly from high rpms this is when the most pressure ocurs on the tensioner the self adjusting qualitys of the stock tensioner are helpfull in reducing wear on the cam chain i could go into all the technical reasons but wont.

What does Ron Hamp know anyway!

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I got the pro and ended up using an allen/socket and fingers to adjust it, I liked the lower clearance than the standard one Jeff pictured and I hear it leaks less oil due to an internal Oring design.  So far after following the install instructions then once I got enough info here to correctly adjust it I have no problems and no leaks.  Its on the same site as the one he pictured.

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I got the pro and ended up using an allen/socket and fingers to adjust it, I liked the lower clearance than the standard one Jeff pictured and I hear it leaks less oil due to an internal Oring design.  So far after following the install instructions then once I got enough info here to correctly adjust it I have no problems and no leaks.  Its on the same site as the one he pictured.

 

the long bolt ones are MUCH easier to adjust however. I have used the long bolt APE models for years, dirt and street. I too thought the slim flush look would look cool so got one for my 08crf450. It's much more tedious to get adjusted correctly, as you have to loosen the two 8mm bolts that hold the mcct to the cyl and get a "feel" for 3mm of tension, then bolt it down. The large bolt design, you loosen the lock nut, rev the running motor, turn the bolt in by fingers till it's pretty snug (slacks up on decel), then back out 1/8-1/4 turn. Done. EASY. I won't be buying the sleek/slim design ones any more.. (and they are more expensive)

Edited by MELK-MAN

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the long bolt ones are MUCH easier to adjust however. I have used the long bolt APE models for years, dirt and street. I too thought the slim flush look would look cool so got one for my 08crf450. It's much more tedious to get adjusted correctly, as you have to loosen the two 8mm bolts that hold the mcct to the cyl and get a "feel" for 3mm of tension, then bolt it down. The large bolt design, you loosen the lock nut, rev the running motor, turn the bolt in by fingers till it's pretty snug (slacks up on decel), then back out 1/8-1/4 turn. Done. EASY. I won't be buying the sleek/slim design ones any more.. (and they are more expensive)

 

Attached TT MCCT Instructions. 

 

JL

TT MCCT Instructions.jpg

0910131909.jpg

0910131910.jpg

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After reading all the stories here I thought I'd get at least one MCC.

I've never had a problem with any tensioners in the 5 years we've had Honda dirt bikes.  

But I figured I got a lot of dough in this 13 motor so what the F.

Also after giving it some thought, I decided the cam timing might be slightly more consistent with the MCC, but don't really have a way to prove it either way.

I jgot the APE Pro. I thought the Pro version looked more professionally engineered in the pictures than most of the others. 

I'm a little disappointed  that the adjustment, and lock nuts are US standard sizes and not metric. WTF?

So now I got to have a 1/2 or 9/16 wrench handy when I do any top end work.

 

Anyway I haven't installed it yet, but at first glance on the 13 it looks as though there might be some interference with the capacitor (or whatever Honda calls it).

Has anyone installed the MCC on a 13 yet?

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that's weird.. i currently have 3 APE mcct, 2 for roadrace bikes, 1 on my 04 crf450r, all are 16mm metric adjusting and locking nuts..

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the pro lock nut seems standard also, 5/8 or 11/16 a(don't remember) and the allen head seems to be metric.  I can adjust the pro one the same way as the instructions Falcon1 posted by using the allen socket and no oil on the tools or fingers.  However I ended up using the instructions from Jeff at Bigborethumpers by setting it at TDC , tighten until just snug the back out 1/4 turn.  Then I backed it out a little and tried it like falcon 1 posted instructions  and it was the same.  I have never tried it running. but doing it TCC seemed easier than adjusting while turning it over.  So far so good

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the pro lock nut seems standard also, 5/8 or 11/16 a(don't remember) and the allen head seems to be metric.  I can adjust the pro one the same way as the instructions Falcon1 posted by using the allen socket and no oil on the tools or fingers.  However I ended up using the instructions from Jeff at Bigborethumpers by setting it at TDC , tighten until just snug the back out 1/4 turn.  Then I backed it out a little and tried it like falcon 1 posted instructions  and it was the same.  I have never tried it running. but doing it TCC seemed easier than adjusting while turning it over.  So far so good

 

Ram,

 

If you run the bolt all the way out of the MCCT with your fingers, then run it back in with your fingers you will eventually feel when the bolt makes contact with the cam chain. Once the bolt starts to load up, run it in until it gets snug against the cam chain, then back it out 1/4 turn. You should be fine.. just practice running the bolt in until you feel it load up against the cam chain, then back it out the 1/4 turn. 

 

You will know when it's right. Not too loose, and not too tight. 

 

Let us know when you get it figured out. 

 

Piece of cake.

 

JL

0909131809.jpg

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^^ good luck with that method if you use the flush manual cct. The one that doesn't have a long bolt with a big nut at the end. It's a small flathead screwdriver bolt or allen, and you can not "feel" when it makes contact with the cam chain guide.. (a tensioner never actually touches the cam chain).

The flush design requires you to adjust the center bolt and use the 2 mounting bolts to establish 3mm or so of distance form the tensioner body to the cylinder, then bolt it down. way more difficult to get right easily. Not that it wont' work, just not as easy as the cheaper models that have the long bolt sticking out the back.

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I had 2 failures of CCTs, one took the whole top end with it, cam, valves, cylinder, piston, etc...

 

I only run manual ones now, I just take the stock one tap it and make my own, pretty easy actually.

 

Also its a good idea to change the chain once in a while as well..

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^^ good luck with that method if you use the flush manual cct. The one that doesn't have a long bolt with a big nut at the end. It's a small flathead screwdriver bolt or allen, and you can not "feel" when it makes contact with the cam chain guide.. (a tensioner never actually touches the cam chain).

The flush design requires you to adjust the center bolt and use the 2 mounting bolts to establish 3mm or so of distance form the tensioner body to the cylinder, then bolt it down. way more difficult to get right easily. Not that it wont' work, just not as easy as the cheaper models that have the long bolt sticking out the back.

 

Melk,

 

I agree..

 

The CCT does not actually touch the chain; however, it pushes against the back side of the cam chain guide which the chain rides on. I can easily feel my MCCT load up (tension) with my fingers when it pushes against the cam chain guide. I run it in until it's snug, (not too tight) then back it out approximately 1/4 turn or slightly less. 

 

I cheated when installing my MCCT.. I had the engine out of the bike, left side crankcase and flywheel removed, and I could see straight down into the cam chain housing through the head while adjusting the MCCT. Once we had the proper tension on the chain, I marked the exposed threads on the MCCT bolt. That way, all I had to do is run the bolt in to the mark and it was good to go. 

 

JL

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