Is a manual timing chain adjuster available for a 2007 YZ250F?

Is there a manual timing chain adjuster available for a 2007 YZ250F?

I am really concerned that if the timing chain lost tension when the

throttle is let off of quickly as claimed by aftermarket companies,

that every thing that I have been doing is in vain to prevent a

catastrophic failure.

Furthermore, it really burns me that Yamaha would correct a faulty center intake valve on

a previous model (06') with a free valve replacement, and then turn around and continue

the use of an auto adjuster that has the potential and catastrophic

possibility of costing someone $1200 every time it does jump timing,

because of the loss of tension. Aren't the tolerances supposed to be built

into the specs to allow for this scenario? From what I understand,

aftermarket companies are using scare tactics to make people believe that

engineers had no idea what they were doing when I bought a well oiled

machine. And if that is or isn't the case, does anyone have the actual

numbers as to the probability of how often this happens? To me, this is

similar to building the perfect bomb, but having no idea how to build the

timer for it so that it doesn't blow your a$$ up. Now I am really looking for

constructive input on this one please. I am not knocking Yamaha or

aftermarket companies in any way, I just am about to finish a completely

new bottom and top end, and here it is I find that built-in tolerances may

not cut it when it comes to something as crucial as this valve train. I have

read that Yamaha has one of the most reliable valve trains on the market

and from personal experience, I couldn't agree more. A $60 manual adjuster

is cheap insurance for a $2280 rebuild if it is available for a 2007 YZ250F.

Thanks in advance for your input or thoughts.

Edited by nokickstandsallowed
I looked closer at the '06 valve recall threads.

APE has manual CCT's.

Yes, a MCCT is significantly better than an ACCT. However, it is one more thing for an owner to adjust. Not that once they are set, they ever should have to be readjusted except when the cams are removed. But people cannot keep their fingers off stuff, esp. those that are clueless. Give a man a pair of pliers and lock the door.

You are supposed to replace the adjuster every time you replace the cam chain. People tend to replace the cam chain every time the barrel is removed, on some bikes, that is every 30 hours. So people do not swap them out. They should be replaced every 100 hours though. But the reality is, no one ever replaces them until they tragically fail.

APE has manual CCT's.

Yes, a MCCT is significantly better than an ACCT. However, it is one more thing for an owner to adjust. Not that once they are set, they ever should have to be readjusted except when the cams are removed. But people cannot keep their fingers off stuff, esp. those that are clueless. Give a man a pair of pliers and lock the door.

You are supposed to replace the adjuster every time you replace the cam chain. People tend to replace the cam chain every time the barrel is removed, on some bikes, that is every 30 hours. So people do not swap them out. They should be replaced every 100 hours though. But the reality is, no one ever replaces them until they tragically fail.

I saw the APE manual adjusters, but didn't see one listed for when the aluminum frames came into play. Very interesting to find out how often that adjuster should be replaced - Thank You Very Much Indeed William. I have very little experience with these four strokes as you are aware; but, I definitely know now what not to do as far as certain things. Do you have an applicable link that perhaps I missed? Thanks Again.

I spoke with APE. The kid that answered did not know. I did look up the part # for an 03

5TA-12210-00-00

and an 08

5TA-12210-20-00

Same part. If you ordered an 5TA-12210-00-00 from Yamaha, you will get an 5TA-12210-20-00 . The difference is a superceded part. Can be an internal change, can be merely paint color. But they are interchangeable mechanically. So... an APE #YT1000 will work fine.

I spoke with APE. The kid that answered did not know. I did look up the part # for an 03

5TA-12210-00-00

and an 08

5TA-12210-20-00

Same part. If you ordered an 5TA-12210-00-00 from Yamaha, you will get an 5TA-12210-20-00 . The difference is a superceded part. Can be an internal change, can be merely paint color. But they are interchangeable mechanically. So... an APE #YT1000 will work fine.

That was fast! THANK YOU for taking the time William. That was a clever idea about the years you looked up - I never would have thunk it! I am quite a bit concerned when it comes down to those numbers, as I know nothing other than to see if they are identical in parts fiche finders (stock). If they aren't, I get nervous for the kind of money I already spent, not what I am going to spend on aftermarket parts, if I can prevent something down the road.

Almost all manufacturers use the last digits/characters to denote upgrade/cosemtic changes. If it is a cosemtic change which I beleive this is), it is because the old color inventory is all gone and it was decided to only offer the part in the new color and not stock two identical parts of different colors. Dollars and sense.

If you are ever unsure, give a reputable dealer a old part number and they will tell you if it has a superceeded number. They probably will not know why though. Often, all you can ever see is paint color. Like the old Yamaha silver grey side covers and the ' bold new black'. Some times it is an improved interchangeable design, a better surface treatment or other actual improvement.

Dollars and sense.

It's funny how our language can be used for certain purposes to get a point across even with dual or multiple meanings or even slightly altered for pun intended purposes. - :smirk:. Understood!

Well I see I'm a little late here... this new job I have is killing my thumpertalk time :smirk:

Anyways, the APE mcct is what I have been running for 2 years after my automatic one lost tension and the exhaust cam jumped time (bending my exhaust valves). The APE unit is a nice piece, though the bolt in the center is really long, so it looks weird. I actually shortened mine so it wouldn't stick out so far.

Well I see I'm a little late here... this new job I have is killing my thumpertalk time :smirk:

Anyways, the APE mcct is what I have been running for 2 years after my automatic one lost tension and the exhaust cam jumped time (bending my exhaust valves). The APE unit is a nice piece, though the bolt in the center is really long, so it looks weird. I actually shortened mine so it wouldn't stick out so far.

That is O.K. KJ - Wisdom never arrives late, it arrives precisely when it means to. I am in the process of ordering one in a couple of minutes, and was wondering from the picture I saw, if that bolt could be shortened or replaced. What method did you use to shorten it?

That is O.K. KJ - Wisdom never arrives late, it arrives precisely when it means to. I am in the process of ordering one in a couple of minutes, and was wondering from the picture I saw, if that bolt could be shortened or replaced. What method did you use to shorten it?

What they use is a long bolt and turn the head down so it is round, this end hits against the cam chain guide. On the end that sticks out of the engine they put a nut on it to tighten against the tensioner itself, and then at the end of the bolt they put another nut with a small tube (or set screw, I can't remember exactly what they used) to lock it in place so you can turn the whole bolt. All I did was cut the bolt shorter and then put a new nut with a set screw in it on the end of the bolt.

What they use is a long bolt and turn the head down so it is round, this end hits against the cam chain guide. On the end that sticks out of the engine they put a nut on it to tighten against the tensioner itself, and then at the end of the bolt they put another nut with a small tube (or set screw, I can't remember exactly what they used) to lock it in place so you can turn the whole bolt. All I did was cut the bolt shorter and then put a new nut with a set screw in it on the end of the bolt.

I just looked at their instructions for installing a MCCT from APE - It shows how to do it on a CRF 450. That isn't the problem I am having a hard time swallowing, it is the fact that they state that you can adjust those things while the bike is running, but with a very dire warning. They even went out of their way to warn you - very nice of them. I don't know about you, but if I heard my cam chain slapping things around in my motor, I would immediately shut it down and correct the tensioner. Not mess around with it while the bike is running and have it accidentally lose all tension while running and become the quickest new motor I ever destroyed. A marred cam chain and faulty valve is how I got to this point in the first place. That is scary to think that you could reach down there with two wrenches and back the jam nut off while adjusting the tensioner bolt; but if your in a hurry or forget which way or which one to turn or not turn while the bike is running, kiss it goodbye :lol: - especially if your tensioner wrench slips off from vibrations and the bolt backs out in a flash :smirk:. Although, I don't think that it would happen like that - I could be wrong :smirk:.

I'm still getting one though, I like the danger of fine adjustments like that when the bike is running. Isn't that what riding is all about, fine adjustments at high speeds? :prof:.

One question I have though KJ, did you only finger tighten the tensioner and then back it off a quarter turn before locking it in place like they suggest while turning it over by hand? And have you ever adjusted it with the motor running? Thanks!

Edited by nokickstandsallowed
It is getting late.

This is an interesting thread... I've not heard of camchain tensioners backing off on Yams before. I've been racing WRs since 2002 and never had a problem. One question that springs to mind is how do you set the tension properly on a manual tensioner?

Last year I bought a mint condition WR with just 300 miles on it. Before running the engine I got it home and checked the valve clearances, only to find the timing was out by one tooth. It turns out the guy I bought it off had drowned the engine in a large puddle and had the piston and barrel replaced. But whoever rebuilt it had not backed off the autotensioner when they reinstalled it which had overtightened the chain, stretching it and badly wearing the teeth on both camshaft sprockets and the crank sprocket. Fortunately he took the bike back, but it goes to show what can happen if you overtension the chain.

I just looked at their instructions for installing a MCCT from APE - It shows how to do it on a CRF 450. That isn't the problem I am having a hard time swallowing, it is the fact that they state that you can adjust those things while the bike is running, but with a very dire warning. They even went out of their way to warn you - very nice of them. I don't know about you, but if I heard my cam chain slapping things around in my motor, I would immediately shut it down and correct the tensioner. Not mess around with it while the bike is running and have it accidentally lose all tension while running and become the quickest new motor I ever destroyed. A marred cam chain and faulty valve is how I got to this point in the first place. That is scary to think that you could reach down there with two wrenches and back the jam nut off while adjusting the tensioner bolt; but if your in a hurry or forget which way or which one to turn or not turn while the bike is running, kiss it goodbye :lol: - especially if your tensioner wrench slips off from vibrations and the bolt backs out in a flash :smirk:. Although, I don't think that it would happen like that - I could be wrong :smirk:.

I'm still getting one though, I like the danger of fine adjustments like that when the bike is running. Isn't that what riding is all about, fine adjustments at high speeds? :prof:.

One question I have though KJ, did you only finger tighten the tensioner and then back it off a quarter turn before locking it in place like they suggest while turning it over by hand? And have you ever adjusted it with the motor running? Thanks!

Believe it or not, but the first Suzuki RM-Z450's came with mcct's and the manual said to adjust them while running like that. It said to back it off until it started making a terrible noise, then tighten a little bit and lock it down. Personally I can't bring myself to do this, so I just set the tension when the valve cover is off. I just tighten it up enough that I can wiggle the cam chain up and down between the two cams, but so it is not too loose. I used the stock tensioner to get an idea for how tight it should feel and then have just tried to mimic that feeling and haven't had a problem from doing it that way.

The key to adjusting while it is running is to have the adjustment close before you start it, typically on the tight side. Then you back it off and you'll hear the 'can of washers' sound. Then you tighten the adjusters till most (not all) the sound goes away. As you are tightening it, suddenly, it will get a lot quieter. That is when you stop adjusting. Further adjusting will make it quieter but it puts excess tension on the chain.

I always final adjust with the engine running. After you do it the first time, it is really not that scarry.

Believe it or not, but the first Suzuki RM-Z450's came with mcct's and the manual said to adjust them while running like that. It said to back it off until it started making a terrible noise, then tighten a little bit and lock it down. Personally I can't bring myself to do this, so I just set the tension when the valve cover is off. I just tighten it up enough that I can wiggle the cam chain up and down between the two cams, but so it is not too loose. I used the stock tensioner to get an idea for how tight it should feel and then have just tried to mimic that feeling and haven't had a problem from doing it that way.

The stock tensioner was my first idea; however, I am not buying a new stock tensioner to set up my APE tensioners' tension correctly. I'll just go from the old one (stock) and add a quarter turn tension to the APE instead of loosening a quarter turn since the old one is probably out of specs. I know the general tension that a cam chain must have or not have. Man this thread is getting to be a tongue twister, and I'm not even speaking, I'm typing :smirk:.

KJ - What year of Yamaha's are you running this APE tensioner on, and do you know of any Yamaha's they don't fit on after the aluminum frames came into play. If I missed it in your garage (I didn't see your mods listed), I would like some closure to be visible in the thread to help others make a decision about this tensioner. Thanks!

Edited by nokickstandsallowed
The keyboard and I were fighting for supremacy.
This is an interesting thread... I've not heard of camchain tensioners backing off on Yams before. I've been racing WRs since 2002 and never had a problem. One question that springs to mind is how do you set the tension properly on a manual tensioner?

Last year I bought a mint condition WR with just 300 miles on it. Before running the engine I got it home and checked the valve clearances, only to find the timing was out by one tooth. It turns out the guy I bought it off had drowned the engine in a large puddle and had the piston and barrel replaced. But whoever rebuilt it had not backed off the autotensioner when they reinstalled it which had overtightened the chain, stretching it and badly wearing the teeth on both camshaft sprockets and the crank sprocket. Fortunately he took the bike back, but it goes to show what can happen if you overtension the chain.

The auto cam chain tension/tensioner backing off, is not uncommon when the throttle is let off quickly while in the high rpm range according to aftermarket companies. Whether or not it becomes catastrophic, depends solely on how often you change the ACCT out, as previously pointed out by William1 - some people don't do it until it tragically fails. I like your question about adjusting the tension. "One question that springs to mind is how do you set the tension properly on a manual tensioner?" I don't think a "spring" has anything to do with it, as that is what the auto adjusters use. I'm just being silly, but that initially was one of my questions in a thread from ages ago.

KJ - What year of Yamaha's are you running this APE tensioner on, and do you know of any Yamaha's they don't fit on after the aluminum frames came into play. If I missed it in your garage (I didn't see your mods listed), I would like some closure to be visible in the thread to help others make a decision about this tensioner. Thanks!

I believe the cam chain tensioner is the same for all years of the YZ250F. The frame doesn't matter since the tensioner sits below the carb, and the carb has not really changed over the years either. I've been running it on an 07, but you should be fine with any year.

I believe the cam chain tensioner is the same for all years of the YZ250F. The frame doesn't matter since the tensioner sits below the carb, and the carb has not really changed over the years either. I've been running it on an 07, but you should be fine with any year.

Thanks KJ.

Two questions:

1. Anybody know the website for an APE tensioner? (Never heard of one)

2. Anybody have any feedback on the Tokyo Mods tensioner?

http://www.tokyomods.com/yamaha/99-06%20YZ250F.html

Thanks!

This is the link that I ordered it from; however, the page redirects for security purposes: http://www.bigborethumpers.com/tensioners.html

I have no idea about the Tokyo Mods Tensioner.

:smirk:The Tokyomods one is $100!!!!! :smirk:

Not worth it IMHO. Nice part if you have money you do not want, however, if you have money you do not want, please PM me.

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