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IF IT BLEEDS WE CAN KILL IT ,THIS STUFF WILL MAKE YOU A GODDAM SEXUAL TYRANASURUS ,YOUVE BEEN PUSHING TOO MANY PENCILS DILLON .GET TO THE CHOPPER

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IF IT BLEEDS WE CAN KILL IT ,THIS STUFF WILL MAKE YOU A GODDAM SEXUAL TYRANASURUS ,YOUVE BEEN PUSHING TOO MANY PENCILS DILLON .GET TO THE CHOPPER

My belt lasts long enough, my bearings are cheap to replace.

I see the real need for a sprung tensioner being to reduce load on the output shaft, has there been any reported incidents of these bearings failing ?

If yes, then yes there is a legitimate need for a sprung tensioner, if no, then this may just be a bit of bling.

But I like bling

Can only describe my 1125,it's all I have experience of.
The original design,fixed idler wheel and offset swingarm mount is quite a clever principle.But unfortunately someone appears to have gotten their sums wrong or there are big differences in belt lengths/elasticity.The geometry also shortens the wheelbase under acceleration,which is why it's so easy to wheel spin.downward torque reaction unloads the tyre.

My bike clearly showed very little suspension movement with standard idler setup.Remove idler wheel and the rear end will move as you expect it to.
Clearly belt length is restricting swingarm movement,a sprung idler allows full suspension movement while keeping some tension on the belt.

It is pretty obvious that as soon as you sit on the bike you are putting the belt under high tension,which is only going to increase when drive is fed in.Add a few bumps in and the loads through the belt increase.
The belts are obviously strong enough,so they are trying to move everything else.
The rear wheel bearing is obviously the weakest point and tends to fail first.

My bike is much more pleasant to ride with the sprung tensioner.As the suspension now squats further it appears less prone to spin the tyre.

However it is highly likely that a correctly sized or adjustable fixed idler wheel could correct the problem too.

My experience with the long swingarm and chain conversion show that the swingarm to spindle length just keeps increasing.Meaning I have to wind the suspension right off and compress the spring to it's absolute lowest to set chain tension.This means there is a huge amount of slack when returned to normal ride height.

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Nige...1125d 9.43@140mph

So Maz, why not share your thoughts and give some design direction to Willy to enable him to create a product that will benefit Buell 1125 owners worldwide.

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08 Specialized Langster

on P1 of this thread, Maz wrote.......



However, I believe the current solution fitted to my CR works just fine and costs zero.......before I explain what that is, I have asked questions above I was hoping would provoke some lateral thinking......let's see what folk come up with

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Mithered ta death.
92 MB
96 S2T
98 S1W
00 M2
01 X1
03 P3
10 CR

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FUBAR pilot

You only need two bikes in life-an S1 and a Multistrada!

......it would appear, judging by the underwhelming response to my questions above, that the technically aware members of this motorcycling forum have no opinion as to why they mindlessly bolt accessories to their machines
Obviously, I would've got a better response if I'd joined in with the debate re. bankers bonuses

WB, as you've taken the initiative and actually got of yer arse to address the perceived issue of the need for a sprung tensioner for 1125's, maybe you'd like to explain the design parameters you took into account when building your tensioner ?

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Mithered ta death.
92 MB
96 S2T
98 S1W
00 M2
01 X1
03 P3
10 CR

don't buy an 1125
problem solved

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Feros Ferio

Aw man, how I hate disappointment.

Let's have a think why people have not responded:

1. They know but haven't had time
2. They know but can't be bothered
3. They know but are waiting for someone to respond then join in the discussion in either a positive or negative manner
4. They think they know why but when the blue bird asks the question it puts doubt in their mind and they do not want to be humiliated - They would rather wait for someone else to respond but they want to see the answer
5. They do not know the technical reason but they have faith in those that have told them to fit it - nowt wrong with that. The girl in accounts with the Mercedes has no clue what the word Kompressor means, much to the disappointment of the men in Engineering, other than that her car punishes theirs away from the lights...

I will write my thoughts about the belt and tensioner on Tuber, Fueller and Boiler later tonight. Feel free to beat me to it.

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08 Specialized Langster

6. Their eyes cannot bear to look at an 1125 for long enough to see the problem, and besides, they have a Tuber, which doesn't even have the problem.
That'll be me then.

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'98 M2 Razorback, it's a keeper.

Thanks Pash.
I had responded, but obviously not in the way that was wanted

I think I fit under point no. 5.

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Valencia Orange XB12Scg - serviced by Maz 2018
Black P3 Blast - serviced by Maz and fixed by Maz in 2019

Don't ride it/keep it in a crate?

I fitted 1 because I was told it would make the belt last longer, and reduce wear on the output shaft bearing. I don't believe the making the belt last longer, as the original belt lasted just over 10,000 miles, with the standard tensioner (and I suspect it snapped due to a stone as I had the guards removed), had the FS tensioner fitted a few miles after a new belt, and re-fitted the guards, and that belt lasted not much over 4,500 miles/9 months. Still on that belt having only put about 3,000 miles on it since. waiting to see when the output bearing goes to pass judgement as to whether to revert to original or not....

The simple fix would be a longer belt

And that's why I like chains

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Nige...1125d 9.43@140mph

I take it the xb's have an offset swingarm spindle?

The rear wheel needs to be buried in the seat unit before the 3 spindles line up on my 1125.

If you adjust your rear shock to max spring pressure then you'll get less suspension movement and no belt stretch

Willie's sprung tensioner has definitely improved suspension movement,I have not had any sign of slippage despite trying very hard to abuse the belt on the video run.

Towards the end of the video I was in 2nd gear nailing the throttle then snapping it shut as the front lifted,repeatedly. Heavily loading the belt then completely unloading it on the overrun.

The tensioner is not the finished item but so far appears to be doing the job well.

My previous experience of belts was on a topfuel drag bike,where belts were used for primary,fuel,oilpump and supercharger drives.On the smaller belts tension was considered correct if belt could be twisted through 90degrees.Primary belt was 4" wide and the pulleys were fixed,no tensioner.Pulleys were spaced to give enough tension to allow belt to be slid on.

Willie tells me that in industrial use belts are tensioned to leave minimum sag on top run,but they mainly only have 1 way continuous load.

The standard 1125 fitting is bowstring tight at rest??

What am I missing ?

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Nige...1125d 9.43@140mph