New here what is all this about the Cam chain Tensioner

cupasoop · Post by **cupasoop** » Wed Oct 13, 2004 9:35 am

Just to throw another log on this fire..... Was out in the sticks yesterday chatting to one of our vets who's big into his trail bikes. He's got a couple of pukka trail bikes and a Varadero for the road. Now the Varadero has the same engine as the storm (42mm as opposed to 48mm carbs and about 10 hp less) so I quizzed him about the cct's on the big trailie. He didnt have a clue what i was on about. He knows a few Varadero riders who havnt had any problems. Went home and looked up the Varadero owners club on tinternet. Had a look through their forum and guess what, not one mention of failing cct's! There was a few messages about stalling and clunky first gears so it's nice to know we're not that different. So, questions raised: Does 10hp make a difference? Do the cct's have the same part numbers (maybe someone could check this out)? I'm sure there's more questions but i'm loosing the will to live typing this so I'll pass this on to you lot to discuss further.

http://www.honda-varadero-uk.org/

RQ · Post by RQ » Wed Oct 13, 2004 10:27 am

Oh Cuppa, now you have me theorising....... not a good thing, I'll bore you all to death.
As you lot know, the Storm is my first bike, so having never ridden a trail bike or an evolution of one such as the Varadero, the question I have is; would you rev the engine as high, even on the open road?
The Var maxes out on power at 8000 with 93 bhp (which is 1000 earlier than the stock Storm with a sacrifice of 12bhp)
The Var also maxes out torque at 98Nm at 6000 rpm whereas the Storm seems to max at 93Nm at 7000. All stock figures from the Honda site.
The situation where the CCT's retract and all hell breaks loose in the motor seems to be after a period of high revs. Mine went on a changedown after a run of red lines, others mention after trackdays. Therefore, to stop the CCT failing completely, they need to adjust it so as it can not retract regardless of the situation.
The CC is at high tension at high revs, and only when the revs are reduced does it become slack again, and this is where it all goes wrong. So, to summarise, keep the revs below 4000 and it'll all be grand and dandy.

cupasoop · Post by **cupasoop** » Wed Oct 13, 2004 10:46 am

RQ wrote: So, to summarise, keep the revs below 4000 and it'll all be grand and dandy.

And boring

Bink · Post by **Bink** » Wed Oct 13, 2004 11:13 am

....... my CCT went at 15mph / 2000rpm when filtering through traffic ....

there's that theory blown out of the water. But I did rev it hard during the weekend before... Now I stay well clear of the red line and no problems since (7.5k mls)

... now I am off to buy a lottery ticket.

tony.wilde1 · Post by **tony.wilde1** » Wed Oct 13, 2004 11:22 am

while fiddling around with these ccts i did a little "heath robinson"test....i had an old cct thats done 23000 miles...got the kitchen scales out and made the tensioner rod push against the scale..it read 2kilos....then i tried a new one i got and..it read 3.5 kilos...so...heres one theory...as they get old the spring get s week..hence the strange noises..cos it aint tensioning properly...then...all that slackness and movement will eventully brealk the spring and..boom...the post about some one riding a new one home and the front one going after 50k...well...perhaps..the cct wasnt pre tentioned properly at the factory and then it just retracted???only guessing...please feel free to comment...all insults accepted!!

RQ · Post by RQ » Wed Oct 13, 2004 12:28 pm

Sounds good T, Heath Robinson eh? Didn't know the bloke meself, but he sounds like he knows whats going on! Did you notice a difference in pressure when the tensioner was only lets say 1/4 extended and 3/4 extended? Does it start running out of steam at full extension?

That's what I'm getting at Bink, with the chain at full tension at high revs, the pressure on the guides, and therefore the tensioner is massive. In this state the spring has no work to do as the ratchet is holding it. At low revs the spring is loaded as there is no tension in the chain and the spring has to do loads of work to push against the chain. Major fluctuations from high to low makes it work all the harder, and then pop!! It is probably more vunerable at low speeds following a hard run as the spring is required to work harder. Must check my lottery from last weekend, might not solve all my problems, but it will certainly put a dent in them!

Cuppa, my redline is a target not a warning and I've only put two front ones in and one rear one since I got her over two years ago!! Wooo hooo.

Stormin Ben · Post by **Stormin Ben** » Wed Oct 13, 2004 12:29 pm

RQ wrote: The situation where the CCT's retract and all hell breaks loose in the motor seems to be after a period of high revs.

Its not so much the high revs that causes the problem, but how you come down from those high revs.
If you just shut the throttle and coastdown using engine braking then that puts a hell of a lot more stress on than actually braking.
So the new theory is
Don't shut off early for the corner, leave it til the last minute then brake like a b8stard

RQ · Post by RQ » Wed Oct 13, 2004 12:37 pm

Exactly Ben, when you come from high load (high revs) on the chain to no load on the chain (low revs) the spring has to work to compensate for not having any tension in the chain!! You could always just ride the clutch and keep it above 5k rpm.........

The latest response from honda UK is below:

"
Dear Mr Quinn

Thank you for your recent email. I would recommend you take your bike back to your local Honda dealership for them to check it over.

Regards

Gemma Johnson
Honda Contact Centre
0845 200 8000

Data protection:No more info from Honda

Nature of Feedback:Another motorcycle area

Question/comment:I own a Honda VTR1000 Firestorm, and I have a reoccuring problem with Camchain Tensioners. I am subscribed to a website of VTR owners and almost every one of them can relate to the issue. As it seems an inherant problem in the bike, have Honda an official stance on the matter? Is there a guarantee on parts offered? I would be interested in any comments you have on the matter.
Regards,
RQ.

"

dodds · Post by **dodds** » Wed Oct 13, 2004 12:44 pm

Just got my engine back together after the CCT went causing it to jumping about 16 teeth, cant belive it but i had no valve damage so i'm back on the road, i have also bought a spare set of CCT's so at the first sound of a rattle they will be in. Just thought i'd ask if most of the problems are with the front or back CCT , my front one went and from what i have read the front one does seem to fail first ?????, cheers dodds.

Bink · Post by **Bink** » Wed Oct 13, 2004 12:50 pm

As with all politicians and cooperate companies ...
They avoid the issue and don't answer the question! :mad2

tony.wilde1 · Post by **tony.wilde1** » Wed Oct 13, 2004 1:14 pm

rq..theres is no "ratchet "in then ccts pal...take one apart and have a look or better take a look at this pic ok?cheers.

http://www.abercon.co.uk/vtr1000/galler ... mpared.jpg

RQ · Post by RQ » Wed Oct 13, 2004 1:17 pm

Oh the corporate world cheers me every day. And you wonder why people get upset with big companies!!

Dodds, seems to be the front that goes first all right, I've been through 2 fronts and a rear in just over 2 years. Many theories as to why the front goes, but nothing definitive.

tony.wilde1 · Post by **tony.wilde1** » Wed Oct 13, 2004 3:33 pm

found this on varadero site...anot6her sort of problem with cam chains but not tensioners

http://www.varaderoforum.com/cgi-bin/Ya ... 1078505182

RQ · Post by RQ » Wed Oct 13, 2004 3:38 pm

True about the ratchet thingy, I just don't know what else to call it!

bluesman · Post by **bluesman** » Wed Oct 13, 2004 3:44 pm

so, I read all thread again and - well, I still think that idea I mentioned should work.
We can not prevent CCTs from failing, right? But: we can prevent engine from being damaged by that. So, longer bolt at CCT cap will limit retraction distance and even if CCT will fail, it will not retract completely, therefore will not create much slack on chain -> chances for chain to jump teeth will be reduced to none. Does not cure ilness, but cure symptoms.
The only challenge will be to measure distance to retractable part when engine are running at let say 7000 rpm - to get bolt lenght right.