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Bonneville Centre Stand

Posted By: TriVin

Bonneville Centre Stand - 03/30/13 5:52 pm

Hi
I have the usual twisted centre stand on my '72 Bonnie. An absolute pig to get on and off and still leans a couple of degrees to the left when it's up.
I'm probably going to take it to the local blacksmith to get it straightened but am I wasting my time? Is there a known fix for this problem? I'm thinking an additional strut welded across the legs lower down might help stop it twisting again?
Posted By: Stuart

Re: Bonneville Centre Stand - 03/31/13 1:10 am

Hi Dave,

Originally Posted by TriVin
twisted centre stand
going to take it to the local blacksmith to get it straightened

This is good. :bigt

Originally Posted by TriVin
am I wasting my time? Is there a known fix for this problem?

What problem? confused Essentially the same stand props up T160's, that start out at least 100 lbs. heavier dry! Afaik, the only "problems" are people using the wrong technique to put the bike on the stand and/or using the wrong mounting bolts.

Originally Posted by TriVin
I'm thinking an additional strut welded across the legs lower down

You can't go much "lower down" or it'll foul the rear tyre when the stand's retracted.

Only mod. I've seen, at least in GB, was by the founder of triples specialist L.P. Williams (the eponymous Les) when he was building his T160-based 'Legends' - he added a triangular fillet between the the crossbar and each leg.

Hth.

Regards,
Posted By: Tridentman

Re: Bonneville Centre Stand - 03/31/13 1:33 am

Here in US the most common cause of stand problems is starting the bike while it is on the center stand.
+1 on repairing the stand with mild strengthening but IME the stand is up to the job as long as the bike is not started when it is on the stand.Just a pointer for when you have it repaired and replaced.
HTH
Posted By: DavidP

Re: Bonneville Centre Stand - 03/31/13 2:29 am

I guess I was lucky then. I spent many years starting my T150 on its center stand with no trouble. I also never had much trouble getting the Trident up on its center stand, even while seated.
OTOH: I put the proper center stand on my OIF A65, and I couldn't deploy it, just seemed to be about an inch too high. Perhaps it's just the different size rear wheel?
Sold center stand, use swingarm lift now.
Posted By: Tridentman

Re: Bonneville Centre Stand - 03/31/13 2:55 am

There are at least two center stands for the OIF twins.
One is about 3/4" longer than the other.
Doesnt sound much but as the bike pivots on the front wheel any difference in stand length makes about twice as much difference to the rear wheel/ground gap. So the 3/4" difference in center stand length makes about 1 1/2" difference to the rear wheel/ground gap.
The stands are basically interchangeable so it is difficult to know if you have the correct one.
I have the dimensions of the two types somewhere in my notes.
If you are interested I can dig them out.
HTH
Posted By: BikeVice

Re: Bonneville Centre Stand - 03/31/13 4:48 am

As you say, almost all of the early 650's suffer from twisted center stands, but the problem lies not in the stands but in the stops. The OIF bikes incorporate the stand stops into the mounting ears, which are welded to the cross tube. The cross is very thin and was not gusseted to the down tubes on the early 650's . Starting the bike on the stand, heaving the bike onto the stand or sitting on the bike while eating pie can all cause the cross tube to twist until the stand legs face forward at an extreme angle and the bike leans to one side or another. A quick search of the internet found this photo:

[Linked Image]

Notice that both wheels are resting on the ground and the only thing stopping the stand/mounts from twisting further is the foot peg of the stand contacting the ground. Eventually the primary side mounting leg and ear will stop bending while the timing side continue to do so, then the bike will begin to lean to the right. Also,notice that the bike will need to be lifted quite a bit in order to get off the stand, instead of just pushed forward like most Triumphs. Here's a photo of a bike with straightened and braced stand ears and cross tube:

[Linked Image]

One wheel or the other (depending on the fuel load) is about 2 inches off the ground and I can roll the bike both on and off the stand while straddling it. The solution to your problem lies in straightening both the stand and the cross tube, then bracing the cross tube to prevent twisting. I have both a poorly braced 650 frame and a factory braced 750 frame I'll post pictures of in the next few days, if anyone is interested.

Eric
Posted By: DavidP

Re: Bonneville Centre Stand - 03/31/13 5:52 am

Thanks to both of you, that's exactly what happened with this stand. Seller said it was off a '72 Triumph, and it had the curved brace. Tough to tell anything with only the casting number to go by.
With this stand mine went even further forward, had to jack the bike up to get it off the stand. mad
Besides that, the deployment tang was in the way of deploying the side stand with my foot. I've also read here the opinion that the unbraced stand can contribute to frame cracks.
For now, I shall do without. Only a problem if I have a flat on the road.
Posted By: 6T

Re: Bonneville Centre Stand - 03/31/13 12:56 pm

This is a police type stand I have on my 1966 6T to which I added a BMW K75 'bump-stop' to save the silencer getting bashed every time the bikes taken off the center-stand.. Also,the stand will bend if you 'pivot' the bike around(in the garage,say)but it can be corrected by reversing the rotation,if you get what I mean???Anyway,good luck...
[Linked Image]
Posted By: Irish Swede

Re: Bonneville Centre Stand - 03/31/13 3:22 pm

Back in the 1060's and '70's, the dealers instructed us to kick-start our Triumphs ONLY on the center-stand. That's because the side-stand lug was not strong enough to use when starting the bike, and why so many frames have had it broken off.

The picture of the '71 Bonneville, showing the center stand angled so far forward, is also the typical problem of 1954 to 1962
pre-unit Triumphs. The stops on the stand legs are too short.
A good welder can add some material to each side and, with careful fitting and filing, this can be corrected.
Posted By: triton thrasher

Re: Bonneville Centre Stand - 03/31/13 3:49 pm

Best start it on no stand, I guess.
Posted By: Stuart

Re: Bonneville Centre Stand - 04/01/13 12:07 am

Hi Richard,

Originally Posted by Tridentman
the most common cause of stand problems is starting the bike while it is on the center stand.

Like David, I never had a problem with the T160's centrestands caused by starting the bikes on them (before I upgraded the alternators and could almost always use the electric); if I have to kick-start a triple, I almost always have to do it on the centrestand because I suffer from Duck Disease ...

Regards,
Posted By: 6T

Re: Bonneville Centre Stand - 04/01/13 5:30 pm

..heres (a rather bad)factory poster?
[Linked Image]
Posted By: Tridentman

Re: Bonneville Centre Stand - 04/01/13 9:12 pm

I did preface my comment by saying "Here in US-------".
It is a fairly common sight here to see a 300 lb rider trying to kickstart a Brit bike with it on the center stand or worse still on the side stand.
The stresses on the fixings of the stand to the frame are enormous and it is no surprise that problems happen.
I believe that the stand/frame fixings are designed for holding the bike up not for kickstarting it on either stand.
When I started riding a bike in UK (more than 50 years ago) it was drummed into me to stand astride the bike with both stands up in order to kickstart the bike.
Especially so I guess because the only bikes we could afford then were clapped out with stands hanging off the bike.
But--seriously guys--these bikes were designed in England where the culture at the time they were designed and built was to start them with both stands up.
HTH
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