[Engenia]

This probably applies to the TNT as well, but all you Tornado owners should have a look at what I've discovered about the Cam Chain Tensioner. It's a bit long and detailed, so I've added a link to it on my home page HERE. Follow the link under "Serious Stuff" to "The Cam Chain".

I reckon this describes the reason for the 2 cam chains breaking, and 1 skipping a tooth.

It also describes how to set your mind at ease. Read on .... then come back and tell me if you reckon I should go looking for my medication!

 

[colintornado]

I will check my tensioner as soon as i get the chance and i will send details.
by the way give me a clue as to what may be wrong with the wiring diagram ? i will have to get a italian/english dictionary.
I just looked again and it appeares that the neg from battery goes to both sides of the light relay coil !.

 

[Engenia]

You've got it in one, Colin. Can't see how it can work.
I've been meaning to trace it out next time I have the tail off, but it's been, what, 5 months? Somewhat of a record really. She was getting totally starkers quite regularly there for a while.

 

[colintornado]

Just a note if you are doing the tensioner check
My bike is an R S the spring sticks out a fair bit more than engenia found, so put some rags around and support it as you remove the nut, or you may drop it down the back of the engine...
when I put it back i pushed the nut in with one hand and held it pushed in and used long nose pliers to start the thread, griping on the wider part next to the flats..
I have emailed specs engenia..

 

[Engenia]

Have 4 measurements so far.

3 Tre's have available plunger movement between 0.4 mm & 1.4 mm. If the springs were longer, the possible movement would be 8.5 - 9.5 mm.
These Tre's have only 1-2 notches of adjustment left before the chain starts to run slack. Distances range from 11000 to 24000 km. [This is cause for concern, and indicates that they need to be checked.]

1 RS has an available plunger movement of 22.9 mm, allowing it the full plunger movement. It has only 3500 km on the clock, and the plunger can still move 11.5mm. [Looking good.]

We need more info fellas.

 

[aussievtr]

chain

I'll suss mine out near xmas or over the xmas ny period

 

[colintornado]

Re: chain

Just been discussing the cam tensioner thing with Lloyd, has anyone got part number list ? If so we could see if the spring is an identical part listed for all models.
Could the ratchet mechanism be the cause? ie allowing the tensioner rod to be bounced back on the spring and knackering it and causeing it to shorten? Hmmmmmm...

 

[Engenia]

Re: chain

Colin,
I don't have any part numbers, but JohnnyO has raised the issue with Benelli.
The ratchet mechanism seemed pretty secure to me. Once the spring has pushed the plunger forward enough for the next notch to engage, the pawl locks it solid for any reverse movement. Tax's adjuster from his old engine was working just fine. Whether the spring was pushing it far enough is the issue as far as I can see. We'll only get a handle on that by collecting data on engines that are still running. Measurements every 5000 km will show the chain wear trend, and, whether the spring length decreases as it ages (unlikely).
So far there's not enough data to draw any conclusions.

 

[colintornado]

Re: chain

Keep up the reserch then mate, it is certainly an important thing that needs an answer... keep us informed.
Come on everyone check your tensioner spring....

 

[FiBlues]

Up

Any news ?

W: Pekka

 

[Engenia]

Cam Chain Tensioner update

Not much to report really. Only have 6 responses, including 1 for a TNT & another for an RS (both in excellent shape). I wouldn't mind betting that the tensioner is the same right across the range. Spring lengths vary from 75mm (TNT) to 54mm.

AussieRS may be finding more out soon, as he will be talking direct to the factory shortly, for his newsletter.

I'm keeping close track of my new chain. I've documented it here. I've now done an extra 2000km, so it's time I checked it again.

 

[johnyrottin]

Le

I don't have enough technical know-how to help you out or else I would. If someone is in england and wants to come and rip mine down to add it to the database Im more than willing. In fact, Eng. if you want to come ride around england a bit you could come do it! Free room and board!

john

 

[Engenia]

Any volunteers for UK measurements?

Hey John, thanks for the offer. The thought has crossed my mind a few times.
Not sure how far Colin is from you, but I'm sure he could measure yours up.
What do you reckon Colin?

 

[colintornado]

If I am heading his way I will give John a pm, I am a bit to far away to pop in, as he lives at mildenhall I believe ?