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Discussion Starter · #1 ·
I think the centerstand on my 1971 Bonneville may lean too far backward in its down position; it leans at maybe 20-25 degrees off plumb and both tires are sitting on the ground.





It looks like the resting position is defined by flats on the centerstand that are meant to rest against the front edges of the frame tabs, yes?

I've heard/read the OIF centerstand arrangement can be weak, and some winter or another i have half-hearted plans to get reinforcing gussets welded in for both these tabs and also around the bottom of the main frame/oil tube. For now, i can't find any cracks that would explain this current situation.

Since disassembly and finding a professional welder are a long way off (and might possibly never happen): am i right in thinking that the reason the centerstand cants past what I assume was its intended position when in use is because metal has been displaced or worn away from the stand and/or the tabs? If so, would it be safe to lay a few beads of weld on either of them to get things back closer to appropriate geometry?

Or... any other advice would be great. Thanks in advance.
 

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there are several areas that can cause the stand to "sit" wrong -- the tabs on the frame can bend towards the front of the frame ; later models had extra strengthening tabs to help prevent this -- the holes in the stand can wear oversize . as can the holes in the frame tabs - even the bolts can wear -- as yours is an "early" frame it could be that the frame tabs have moved
 

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Discussion Starter · #3 ·
thanks very much, wol. i just had it apart and can confirm that if there's any wear or distortion to the holes in the tabs, threads in the stand, and/or bolts its minimal - and certainly not enough to allow any discernible play without the spring or to account for the rest of the lean.

... which precipitated some more research, yielding this and this, both at BritBike.

Or specifically [borrowed photo]:


so it looks like I need to take a closer look for cracks not between the tabs and the crossmember but between the crossmember and the frame rails. i'm now assuming that the only remedy here is to get these reinforcements, or something similar, done.
 

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Discussion Starter · #4 ·
my new request for help from all of you, then: how complicated of a job is this? my untrained and largely ignorant eye says the hardest part is getting things back into the proper geometry and that the welding itself shouldn't be too hard.

the thread referenced above attributes the work in the picture to Don Hutchinson, and I'm only about 800 miles from him (?). i don't trust myself to do this sort of structural work; does this seem like a project for any decent welding shop or should i be looking for someone with more specific experience?

thanks again!
 

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you are correct - the only critical part is getting the tabs back to where they should be - and more important that both are in the same position otherwise the stand will be in twist - unless you have another frame to reference getting them moved to the correct position could involve some "trial and error" -- the cross tube the tabs are welded to will have twisted / rotated ( there may not be any cracks) - this will need to heated to cherry red to get the metal to move back -- the rest of the work ; making and welding the strengthening pieces is a straightforward job that most welding shops could do
 

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Hi therabbithole, Maybe this can be of some help? looking at my '73 frame, if you take tape measure & go from front lower edge of stand bracket to center line of lower eng bolt, holding tape at bottom of bolt I get 2 11/16" Possibly you could check for bending of brackets/frame that way??

Looking at the factory welded on support tabs they are different from the added on ones in photo. The factory ones are welded to outside of tabs as in photo, but are positioned flush with bottom corner of bracket. They are not square, but curved to the tube. The curve may be a little stronger than the sharp 90deg. bracket in photo. For sure being down to the corner gives more support.

However... The most important part is the position of the weld on. It must be flush with bottom of bracket as the weld on actually becomes part of the stand stop in a direct way. So not only does the flat part of stand in your 2nd photo is the stop, but the weld on becomes another more positive stop so it actually stops against both.

I can't see the outside of your stand in your photo, but my stand has a stop on the outside surface that is machined flat that is made to hit the weld on support as the additional stop. I didn't check part #s of our stands to see if different. If needed it might be good to go with later stand when you weld the brackets on.

I use my center stand often & often start motor while on center stand. I always use center stand in garage & side stand while out riding. I ride 3-4 times per week on average. So far it's done well & holds wheel off ground as from new. I have stock size k70 tires. Looking at my stops & checking bolts for play. Stops look unworn on my bike. Yours don't look worn either. My bolts have some play. I don't know how much is normal, but they are not a tight fit in pivot holes.
 
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