RS mechanical cam chain tension problem bulletin

[grizztracks]

I kinda doubt it. Seems like a hydraulic tensioner would need a dedicated source of oil to function properly and I can't see how something like that could just replace the existing tensioner.

I recall reading something about different colored paint differentiating the old and new tensioners.

Hydraulic tensioner (oil filled) are used by Yamaha. The advantage is that they do not need periodic adjustments due to wear. A hydraulic tensioner applies a more consistent pressure and does not need adjusted over time therefore I would consider it to be big upgrade. All 08 sleds and newer have an upgraded tensioner and the old type has been discontinued for all 05-07 three cylinder engines.

here is an article about tensioners from Yamaha.
http://www.yamaha-motor.ca/technology/t ... &tech=ACCT

Parts Identification
The tensioner can be identified by a paint mark on the tensioner housing. The new type tensioner is identified with a blue mark; the old type tensioner mark is orange.

 

[AKrider]

I agree that a hydraulic tensioner would be a nice upgrade. Thing is, where is the oil going to come from to pressurize it? If the motor was designed around a mechanical tensioner (spring tension), than how does a hydraulic tensioner take its place without some type of dedicated oil passage feeding oil to it? I just don't see how a hydraulic tensioner can simply be dropped in to take the stock ones place.

 

[mbw919]

Hydraulic tensioner (oil filled) are used by Yamaha.

Interesting. Which models?

Just for fun, I looked up the following tensioner numbers on Yamaha's online parts catalog:

• '06 Vector 8ES-12210-00-00
  '09 Vector 8ES-12210-01-00
  '09 Apex 8FP-12210-00-00

According to this web site, the 3 digit prefix is the model code. So does that mean that the Apex uses the same tensioner that is causing problems on the 3 cylinder engines, or are 8ES-12210-00-00 and 8FP-12210-00-00 two different parts?

 

[grizztracks]

I agree that a hydraulic tensioner would be a nice upgrade. Thing is, where is the oil going to come from to pressurize it? If the motor was designed around a mechanical tensioner (spring tension), than how does a hydraulic tensioner take its place without some type of dedicated oil passage feeding oil to it? I just don't see how a hydraulic tensioner can simply be dropped in to take the stock ones place.

A shock absorber is a hydraulic dampening device. To be hydraulic it doesn't need an oil source and pump to pressurize it. The tensioner is filled with oil then sealed and uses porting to control its movement. I'm no expert in hydraulics and have not yet changed it in my 05 Vector. I don't want to take a chance on destroying the engine for a $100 part and some of my time to replace it so I'll probably replace it in the next few months (unless I trade it for the new FI engine).

I've read that when it starts going bad you can actual hear it. My problem is that the clutch is so loud its hard to determine if there is any internal engine noise.

The link I posted is actual a Yamaha motorcycle technology article describing cam, chain and tensioners. It refers to an oil filled automatic tensioner (hydraulic)

 

[grizztracks]

Hydraulic tensioner (oil filled) are used by Yamaha.

Interesting. Which models?

Just for fun, I looked up the following tensioner numbers on Yamaha's online parts catalog:

• '06 Vector 8ES-12210-00-00
  '09 Vector 8ES-12210-01-00
  '09 Apex 8FP-12210-00-00

According to this web site, the 3 digit prefix is the model code. So does that mean that the Apex uses the same tensioner that is causing problems on the 3 cylinder engines, or are 8ES-12210-00-00 and 8FP-12210-00-00 two different parts?

The problem was from 05 to 07 with the 3 cylinder engine. The old tensioner has been discontinued and has been replaced with the one their installing in new sleds. The old tensioner part # has been superceeded.

 

[DaJudge]

Hydraulic tensioner (oil filled) are used by Yamaha.

Interesting. Which models?

Just for fun, I looked up the following tensioner numbers on Yamaha's online parts catalog:

• '06 Vector 8ES-12210-00-00
  '09 Vector 8ES-12210-01-00
  '09 Apex 8FP-12210-00-00

According to this web site, the 3 digit prefix is the model code. So does that mean that the Apex uses the same tensioner that is causing problems on the 3 cylinder engines, or are 8ES-12210-00-00 and 8FP-12210-00-00 two different parts?

The parts will be different between the Vector and Apex.

The breakdown on part numbers is this, 8ES means it is a 3 cyl Vector or RS Nytro. The 8FP means that it is a Apex. The numbers 12210 means it is the chain tensioner or camshaft group. It will be the same for all models. the next numbers, 00 and 01. the 00 means no changes or updates. The 01 means one update. I dont remember what the last 00 is for, it could be color or length something like that.

It was explained to me years ago by a Yamaha parts guy and I may be a little off on the explanation, but that is what I recall. I am sure someone will correct me if I am wrong.

 

[AKrider]

Here are the microfiche that show the cam chain tensioners. To me, they looks like every other spring loaded cam chain tensioner I've seen on Japanese motorcycles and fourwheelers. Unless the existing tensioner is already hydraulic and operated off the oil system (like a lifter in a truck engine) I don't see how the replacement part could be hydraulic and replace a spring loaded tensioner.

An oil filled hydraulic shock absorber does not have any springiness. An oil filled, shock absorber that is gas pressurized does have springiness, but I truly doubt a small cam chain tensioner would be both oil filled and gas charged.

Vector

2009 Apex

[/img]

 

[mbw919]

Just for fun, I looked up the following tensioner numbers on Yamaha's online parts catalog:

• '06 Vector 8ES-12210-00-00
  '09 Vector 8ES-12210-01-00
  '09 Apex 8FP-12210-00-00

According to this web site, the 3 digit prefix is the model code. So does that mean that the Apex uses the same tensioner that is causing problems on the 3 cylinder engines, or are 8ES-12210-00-00 and 8FP-12210-00-00 two different parts?

The parts will be different between the Vector and Apex.

The breakdown on part numbers is this, 8ES means it is a 3 cyl Vector or RS Nytro. The 8FP means that it is a Apex. The numbers 12210 means it is the chain tensioner or camshaft group. It will be the same for all models. the next numbers, 00 and 01. the 00 means no changes or updates. The 01 means one update. I dont remember what the last 00 is for, it could be color or length something like that.

It was explained to me years ago by a Yamaha parts guy and I may be a little off on the explanation, but that is what I recall. I am sure someone will correct me if I am wrong.

Thanks Judge. That's what I suspected the case might be.

 

[mbw919]

Here are the microfiche that show the cam chain tensioners. To me, they looks like every other spring loaded cam chain tensioner I've seen on Japanese motorcycles and fourwheelers.

You're right. They look like the common tensioners used forever on Japanese bikes, atvs, and also modern Triumph motorcycles. Perhaps there was a faulty batch of them rather than a design problem. That could account for the relatively small percent of failures.

Unless the existing tensioner is already hydraulic and operated off the oil system (like a lifter in a truck engine) I don't see how the replacement part could be hydraulic and replace a spring loaded tensioner.

Right again. I think someone has confused "automatic" with "hydraulic".

 

[AKrider]

My motor is verrrrrrrrry quiet... Even the clutch is quiet.. Hmmmmmmmmmmm.. I "WILL" keep an ear open this winter. MM.

Exactly the same here. Never had clutch noise and the engine sounds just right, though I'll be listening carefully this winter.

I talked to my local dealer today and he had to rebuild an engine from the crank up, due to the tensioner failing. I believe he said the customer had around 40k miles and was covered under extended warranty. It's too bad the tensioner isn't easily accessable. It would be a 10 minute job on many motorcycles. Also, this style of tensioner has been used for a very long time on motorcycle engines and I don't recall hearing of problems with them.

Actually seeing the type of tensioner on the microfiche puts my mind at ease. Originally I was thinking the tensioner was similar to the internal one used in the KLR 650 motorcycle and it is commonly thought they have a good chance for failure.

The Yamaha style would be super easy to replace if it was accessible. I've not looked into it, but I wonder if it would be possible to bore a 2" or so diameter hole from under the tunnel, through the close off panel on the bulkhead to access the tensioner? The hole could then be blocked off with a flat piece of aluminum and pop rivets.

Years ago, in one of the Iron Dog races, the winners did the same type of thing on their Cats. At the halfway point in Nome they needed to tighten the a-arm mounting bolts and didn't have access one half of the bolts. They contacted the factory and then knew where to drill access holes into their bulkhead. A couple of holes saved then a bunch of time and they won the race.

 

[Bradford]

Brad -

Did you need to do any removal of coolant/lines at all? And do you think there's a reason to pull the cam cover off the top of motor to take a peek at the chain and cam gears? Keep us posted...if this is a plug and play part I just may change it so I can ride without worry.

The only reason I decided to replace the tensioner was for piece of mind. Doing this job on a Friday night to get ready for a Saturday morning run would just plain suck!

My motor isn't making any noise so I see no reason to pull the cam cover to inspect the chain and gears. I thought I was going to have to remove the coolant lines but I unbolted the coolant bottle and thermostat housing and that gave me enough slack to rock the motor ahead as far as it can go without removing the water pump. I didn't remove the old tensioner yet but it looks like there's enough room to get it out..

Brad

 

[aVenture]

AKrider wrote:

An oil filled hydraulic shock absorber does not have any springiness. An oil filled, shock absorber that is gas pressurized does have springiness, but I truly doubt a small cam chain tensioner would be both oil filled and gas charged.

Like grizztracks said..... dampening.
Torsion spring still in, but oil filling is used as a damper to damaging higher frequency vibration from chain. As an example, oil filled pressure guage in some application can last foreever while standard oilless counterpart need yearly replacement. Oil viscosity have a small impact on which frequency you aim to work with & operating temperature.

The story does not tell yet if the whole thing get into resonnance and sprocket skip a click or then spring fatigue would slowly add sloppiness to the system (which i tend to adhere since it seem you can hear it).

 

[vogelm1]

Brad -

Did you need to do any removal of coolant/lines at all? And do you think there's a reason to pull the cam cover off the top of motor to take a peek at the chain and cam gears? Keep us posted...if this is a plug and play part I just may change it so I can ride without worry.

The only reason I decided to replace the tensioner was for piece of mind. Doing this job on a Friday night to get ready for a Saturday morning run would just plain suck!

My motor isn't making any noise so I see no reason to pull the cam cover to inspect the chain and gears. I thought I was going to have to remove the coolant lines but I unbolted the coolant bottle and thermostat housing and that gave me enough slack to rock the motor ahead as far as it can go without removing the water pump. I didn't remove the old tensioner yet but it looks like there's enough room to get it out..

Brad

I'm in the same boat and just may change it out for piece of mind. Thanks for the tip on moving the engine forward without having to disconnect any coolant lines!

 

[nytrodude]

Has anyone personally replaced the tensioner yet? Just wondering if anything can fall/get out of place when you remove old tensioner. It doesn't look like it would, but that would suck! 06 Nytro w/ blue dot.

 

[grizztracks]

Has anyone personally replaced the tensioner yet? Just wondering if anything can fall/get out of place when you remove old tensioner. It doesn't look like it would, but that would suck! 06 Nytro w/ blue dot.

blue dot on the 06? I've read about others saying they see blue markings also. According to the bulletin they should have an orange dot and the new replacement will have blue.