Tenere Chainguard
 

Has anyone had a problem with the chain coming off. Was stuck in mud and chain came off this weekend and was wondering why the Tenere has no chainguide/guard and if anyone has fitted one.

Do mean chain guide to the back sprocket like on enduro and motocross bikes ?

Errr, funny you should mention that.....

watch this space :047:

Yes, that is what I mean. Peatbog, lets hear it, do you have a solution :icon_question:
I would also be interested to know if anyone else has had this problem.

there is a solution in progress - at the prototype stage. cant say any more than that at the moment partly cos i'm only really helping out with it (there's actually no more to tell until the testing is done).

Thanks, nice to know there's something in the pipeline.

oooh regie i cant agree with you on the chain thing

a certain amount of free play is required,when the swing arm is mid stoke the chain is at it's tightest point,when the suspension is unloaded perhaps when man-handing the bike through rocks/ruts the chain is very easily derailed due to more freeplay [the new bmuu 450 does not suffer].though you are right a slack chain is just waiting to get at the paint!

a chain guide is definitely needed i take great care with my bike and its adjustments and have knocked the chain off on more than one occasion especially on wooded trails.

peatbog,when the guide is ready put me down for one!

Good morning!
Any news on that topic?

Regards

Update? My chain climbed off the rear sprocket and cracked the engine a few weeks ago. The bike will be back on track next week and I would like to sort this out so that it doesn't happen again. Thinking about building something myself and would be interested to hear if someone have made a sucessful mod like this.

i'll be up for one also PB.

JMo was tinkering with one with someone else when she moded her tenere, but the idea seemed to fade away......

:blob8: Calling JMo! Calling JMo!.... was there any outcome on the chain guide idea JMo?

Looking at the pics from the H-L article in TBM, I don't think so.

hi. about seven months and 8500miles ago i made one. it uses the older ktm chain block circa 2002 the genuine is dirt cheap and lasts the longest [years of owning exc's].as it lasts so well it wears the split link so riveting the chain is advisable. has survived very well on proper off road!

the bracket is 3mm stainless plate 52x 65with a right angle fold, so now52x40 with a 25 right angle. the slightly slotted 8.5mm holes where it secures to the swing arm.

the swingarm is drlled to the centre of the flat part,the rear most bolt is app 180mm from the end of the swingarm, i used stainless bolts facing down so easy to remove or repair if damaged on the trail. the bolt heads have a foot welded on to stop them rotating in the hollow of the swing arm. the block is fastened with 6mm bolts the rearmost hole is slightly slotted to adjust to sprocket size

http://i192.photobucket.com/albums/z...llybike020.jpg

http://i192.photobucket.com/albums/z...llybike021.jpg

http://i192.photobucket.com/albums/z...llybike019.jpg

i hope this helps, very reliable, easy to make and fit.give a good place for the scottoiler too. any probs give me a shout, stoic

See Stoic's pix above - this was basically the idea that I was working on too (using the KTM block), and I sent the block and design to Petebog months ago - unfortunately he's been busy with 'real life' and not been able to progress things further I understand...

To be honest, I've never found it necessary on the Tenere - however, in sloppy muddy conditions, I can see it might have a benefit... either that or I'm just lucky*?...

("It's not luck, Todd...")

J x

ps. I can see a nicely fabricated bracket/kit developed one day, utilizing the cheap-as-chips- nylon KTM pattern blocks from Race Spec?

Bad luck for me today. Riding to work this morning, chain came off 3 times. I turned around at the second incident and went back, going at 50km/h constantly avoiding any slightest movement on throttle control.
Still need to take a look at sprocket. No idea about engine case damages right now.
Talon cush drive unit looks scratched badly on the outside (left from chain).
Swingarm got several bad scratches. Chainwheel looks totally damaged.

Story: I did chain maintenance recently. After that I only did some short test rides with a new muffler. Today was the first normal ride. Chain and chainwheel looked good, no bad wear at all. Chain had 16000km, nearly no offroad. Chainwheel had 11000km.
But obviously my chain is at end of its lifecycle and got stretched extremely within the latest few kilometers, which I was not aware of. When coming off the chainwheel the latter also got damaged badly.

I have already got a supersprox chainwheel and ordered a DID VM chain today, also a new sprocket.

Need to check engine case tonight. Hope there is no problem there. With chainguard mounted, the chain would never have come off the chainwheel under these normal circumstances. I would definitely consider installing one, if I can get hold of one.

Phil

That sucks I hope your wheels/sprokets survived

chains should'nt be doing this under normal usage !

http://s1.postimage.org/11p5v1ix0/kettenblatt.jpg

Reason still unknown. No installation issues. Everything was fixed ok, hub, cush drive, sprocket, chainwheel bolts, wheel, swingarm. Chain had some slack, but not really bad. Chain btw. is within Yamahas limit of wear. Sprocket looks good. No idea what destroyed chainwheel (which looked good this morning, left side of picture).
Maybe chain started to slip through on it, teeth got shaved off and chain did no longer reliable stay in its place. I will definitely take this chainwheel to the shop and look at the strange wear. Probably there is a problem with chain line, wearing it off onesided. Maybe we need to grind a little more off the Talon cush drive.
I am sad about those scratches visible at the cush drive unit. But on the other hand, this unit could be replaced easily in case. Not cheap, however.

Regards, Phil

hi flatboarder, that looks very odd and a big pity the hub is marked, tho it could have been a lot worse, if the retaining bolts were yamaha's design [unlike your countersunk type] the damage would be more your swingarm

i guess it's an alu sprocket which i dislike as they can deteriorate very quickly [possible cause], the type you now have are really tuff and can outlast a couple of chains. is your engine sprocket good?

it has to be said a chain guide would do more good than harm, why yamaha never fitted one is beyond me!

bernard

Yes, you are very right. Actually I was quite happy chain did not get torn into it badly.

Engine sprocket looks perfekt. Really.
I used Aluminium chainwheels formerly with my KTM LC4 and EXC. There were no bad experiences apart from the need to replace them if they wore out. But that was visible.
In my case yesterday, I was totally surprised, and I really need to check chain line for correctness. Something destroyed the chainwheel in very short time without a warning before. Maybe just a matter of chain slackness or the new exhaust can with a little bit more torque at lower revs, I cannot tell.

Right. I need to find a solution similar to yours. Main problem actually is getting that small L-shaped piece of tin (shaping, drilling) and fitting it to the swingarm. I have no clue about metal works. The chain guard is no problem, easily obtainable for small money.

Regards, Phil

Would something like this work located close to the rear sprocket?
Probably better with a spinning nylon wheel but the concept would be OK and it also means you wouldn't need to accurately set the chain tension.

http://www.trialsbits.co.uk/product_...roducts_id=498

rob

The problem with a tensioner like that is that since it presses on the chain, it would wear through very quickly on a bike used at high speed (on road) and over any distance - trials bikes by their nature don't cover many miles, and not at high speed...

Jx

We are currently brooding over an adapter solution fitting the inner side of the left swingarm. It should plug into the inner swingarm holes and reach downwards into the chainline. The adapter could probably provide those eyelets to fix a chain guard or just reach down far enough at both sides of the chain to keep it from laterally escaping its natural position.
Probably a carbon solution. No idea. A mate from xt-660.de who is capable of doing CAD work might probably have a look at it. Otherwise I might try to mold something somehow... well no clue right now. I hope we find a feasible solution, and probably without the need to drill swing arm.

Phil

I'd have thought a spinning, polyurethane/nylon wheel would be OK. A bit like a skateboard wheel with a bearing. It would just need a groove machined round it to locate the chain.

rob

rob in a word k.i.s.s. [or acrinom]

the block design has done about 20,000 miles thats 2 salt fest winters, gritty offroads, fortnight trailing in portugal and a blast in sandy stuff to a place called dakar. methinks skate board rollers may have not done it. but hey i'm willing to be proved wrong!

bernard

I agree with Bernard - there is a reason that every enduro bike uses a polyurethywhatsit block and chain slipper to guide the chain, while any rollers above and below the swing-arm are just there incase the chain 'bounces' during suspension travel...

Ideally, the chain (when you are sitting/riding on the bike) is not actually touching any part of the slipper/guide/rollers - it is essentially floating - and only if the chain moves (or is moved) significantly from it's line do the guides keep it in place... If a metal chain is constantly rubbing on a plastic/polyurethane block, it will soon wear though, particularly at road speeds...

This also happens if you run an oversize rear sprocket too close to the lower guide block, and the chain rubs on the trailing edge - in such circumstances, rally bikes can eat a guide block in a day or less...

Jx

This also happens if you run an oversize rear sprocket too close to the lower guide block, and the chain rubs on the trailing edge - in such circumstances, rally bikes can eat a guide block in a day or less...

sounds like the voice of experience!

Hee hee - not me, but I know Tamsin had a lot of problems with the chain guides eating themselves in 2010...

Jx

ps. and I'll say it before anyone else does - guess I didn't get far enough for it to be a problem this year... ahem. (even though I'd ridden over 3000kms x)

..well i got roud to fitting me guide ..and thanks for the great idea

99p off ebay [only bidder ] he he

ive fitted it a little differently or cheated ... depends on you point of view

so far its been fine and a great place for the scottoiler feed

the advatage advantage is its easy to remove if it gets banged up and easy to replace without having to split the chain ..which is a pain in the ass

all i did was punch out the spacers with a 6ml bolt split the guard with a hacksaw ..a bit of wd helps when sawing ..

fitted tyhe brackets as described and put the guard over the chan and repressed the spacers bac in afterwars
[i filed them slightly before so they are flush ]

thats it at the moment its seems to make no difference nice and secure ect ..if anyone was carrying a spare it would only take 5 mins to put it on

http://img62.imageshack.us/img62/7756/img1800i.jpg
By minkyhead at 2011-03-14

http://img220.imageshack.us/img220/7035/img1801v.jpg
By minkyhead at 2011-03-14

http://img97.imageshack.us/img97/5127/img1802pm.jpg
By minkyhead at 2011-03-14

http://img687.imageshack.us/img687/6830/49200133.jpg
By minkyhead at 2011-03-14

hi minkyhead, yup thats the ticket, nice job!

although i havn't done it to the tenere guide, running the saw through the block is the best for replacing/ removing as i always rivetlink the chain

last weekend i was doing a h&h on the gasgas, just a 2 hour event and after 1.20 the chain was derailled with a stony slurry type mud on an overtake out of a slow corner. the chain was so mangled in around the front sprocket it needed the swingarm to be removed. obviously after a long push and retrieval home.
unfortunately it's not just a chain needed it broke 3 teeth off 1st gear and that needs a new shaft as well as a corresponding gear on the output side ho hum and i was leading the expert class passing a backmarker such is life!