bouncing center stand

I both love and hate that I have to figure stuff out on my own much of the time. Sometimes it's more rewarding to just make the parts to copy someone elses proven design. It's rewarding to make something that you can see already works. I am considering a double spring set up for the center stand because it bounces down.. I'm sure it does that because I have a stiffer than normal suspension. Maybe a bouncing centerstand is less of a problem on softly suspended bikes. I would think that's a physics thing.

Anyway, I was thinking a second spring, but that might just make it bounce against the frame with more force, so I'm also thinking a clip to hold it in the up position. I'd rather have it be a mechanical catch to hold the stand rather than using a bungee cord. I was wondering if any bikes use a clip to fasten the stand securely in the up position. I googled it and got nothing helpful.

My other answer was to weld up an aluminum center stand so the lighter weight stand would be easily held up by the stock spring, but I'm a beginner at welding metals. I could probably make a steel one like I already have but the aluminum would be new territory. (Concours, what do you think???)

o0norton0o said:

I both love and hate that I have to figure stuff out on my own much of the time. Sometimes it's more rewarding to just make the parts to copy someone elses proven design. It's rewarding to make something that you can see already works. I am considering a double spring set up for the center stand because it bounces down.. I'm sure it does that because I have a stiffer than normal suspension. Maybe a bouncing centerstand is less of a problem on softly suspended bikes. I would think that's a physics thing.

Anyway, I was thinking a second spring, but that might just make it bounce against the frame with more force, so I'm also thinking a clip to hold it in the up position. I'd rather have it be a mechanical catch to hold the stand rather than using a bungee cord. I was wondering if any bikes use a clip to fasten the stand securely in the up position. I googled it and got nothing helpful.

My other answer was to weld up an aluminum center stand so the lighter weight stand would be easily held up by the stock spring, but I'm a beginner at welding metals. I could probably make a steel one like I already have but the aluminum would be new territory. (Concours, what do you think???)

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I think you maybe overthinking your centre stand
There's plenty of bikes out there of all makes with single or twin springs on their centre stands that don't have issues
I'd give the double spring a try
If not there must be some sort catch could fit, maybe even a strong cupboard door catch magnetic catch
Making an aluminium centre stand would be difficult to get the strength and could end as heavy as a steel one
But I love fabrication so I'd love to see an aluminium one made

I just made an inner spring to fit inside of the original spring out in the shop... I'll give it a try and see how it goes. It's only 2.5mm music wire. I could go 3mm probably to make it stronger if need be. I don't care if it's hard to deploy with a lot of spring pressure. It's dropped down on a few left hand turns and scraped the pavement... That's totally unacceptable. I can't risk my life just because I made the center stand a tiny bit heavier extending it so it would be a bit longer and work better. (early stands are notoriously a bit short)

I cut off the "lever/push down with your foot" part. It would scrape on the ground in left turns too.
Got rid of the weight of that part and it no longer would bounce off the ground when crossing bumps.
no problem sticking my toe under the muffler to fish it down. Don't need the leverage. Just lift below the seat while pulling back on the left handlebar.

John Laing said:

I cut off the "lever/push down with your foot" part. It would scrape on the ground in left turns too.
Got rid of the weight of that part and it no longer would bounce off the ground when crossing bumps.
no problem sticking my toe under the muffler to fish it down. Don't need the leverage. Just lift below the seat while pulling back on the left handlebar.

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The witness marks on my stand were on the front of the left foot of the stand. I have a 70' model with the weird centerstand. I think I forgot to say that...

I put the center stand back on the bike and I installed the double spring. It's the simplest solution so I got to give it a try. The center stand is great for doing any kind of service, especially tire problems so I do want one on the bike. If I can't make it so it doesn't bounce or drag, I'll just zip tie it up and use the side stand as the primary stand. here's a picture of the double spring. It feels a little stronger than the single and physics says that their force should add up.... giving it a shot...

The double spring did NOT fix the problem. I just ran it through the test course and it bounced down and lightly hit the pavement,.. I"m entertaining skeletonizing it...

o0norton0o said:

The double spring did NOT fix the problem. I just ran it through the test course and it bounced down and lightly hit the pavement,.. I"m entertaining skeletonizing it...

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it looks almost horizontal: right location on bike?

And welding an horizontal steel bar between the stand ala 850 stand and fitting another spring ....? I am looking at your post just because one day I will have to sort out the same problem!

A horizontal spring can't do much to hold the stand up.

Just trying to mimic the 850 one which is not vertical neither horizontal ! may be need another craddle spring location hole ?

marinatlas said:

And welding an horizontal steel bar between the stand ala 850 stand and fitting another spring ....? I am looking at your post just because one day I will have to sort out the same problem!

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For now, I have the centerstand zip tied up against the frame. I'm just going to use the side stand for now and cut the zip tie if I need to put the bike up for service. I'll figure some sort of solution out and post it

batrider said:

A horizontal spring can't do much to hold the stand up.

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I think this is the key to the solution. I'm going to see about raising the angle of the spring on the frame side.... Brilliant analysis Batrider, thank you!

batrider said:

A horizontal spring can't do much to hold the stand up.

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Just checked mine - fore-and-aft (not along the line of the spring) it's pulling upward by 15 degrees.
So, for every 10kg pull by the spring, 2.6kg is going upward.
Methinks the bouncing ones don't have this force - no?

Just a thought.
It's not possible that the bouncing ones have the spring hooked on the rear of the stand cross-member (instead of the front - where it should be)?
If so, that would make the spring pull "almost" horizontal, maybe explaining the bounce?
Cheers

robs ss said:

Just a thought.
It's not possible that the bouncing ones have the spring hooked on the rear of the stand cross-member (instead of the front - where it should be)?
If so, that would make the spring pull "almost" horizontal, maybe explaining the bounce?
Cheers

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It can only go one way.... BTW, it's an early model frame (1970) . The hook for the frame aligns the hook for the stand and the plate with the hole is welded to the frame on one side so the spring hook has to face the clear passage side of the plate, not the "frame side of the plate", so that aligns the hook for the stand in the only direction it can face..

I have a solution...I'll post it when it's done

o0norton0o said:

It can only go one way.... BTW, it's an early model frame (1970) . The hook for the frame aligns the hook for the stand and the plate with the hole is welded to the frame on one side so the spring hook has to face the clear passage side of the plate, not the "frame side of the plate", so that aligns the hook for the stand in the only direction it can face..

I have a solution...I'll post it when it's done

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But... if you made the spring go under instead of over the stand cross-bar in you photo I believe it would create the upward force you're after. No?

o0norton0o said:

It can only go one way....

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Try it as an experiment - I bet it works! ...and don't give me "it only goes on one way" crap. that's only true if you want it to be!

Rob, The spring can only go on one side of the plate. The spring is not clear to swing down with the stand on the other side so it can only go one way...

So,... I tried adding a plate to the existing frame plate with a new hole to create a higher hole for the spring, so the angle of it's pull would be less horizontal and the spring would be pulling more upward, making it harder for the stand to bounce downward. Unfortunately, the bottom bolt from the gearbox cradle interferes with the spring and limits how much I can raise the spring hole. I tried bending the spring and moving it out wider on the stand to get away from the bolt but no matter what I did the higher hole either interfered with the cradle bolt or the spring plate. I may revisit making a new hole at the very upper limit of it's possibility before it hits the cradle bolt as part of the solution, but my first attempt had a fatal flaw. Fixing that flaw entails welding up the new spring hole on the plate I made and drilling another hole only a little bit higher than the original one to get the most spring angle possible before the cradle bolt interference occurs.... I'm learning what works by trial and error as I go here

The other thing I am trying is welding a second spring stop on the bottom of the stand for a spring on the plate on the other side of the gearbox so I can mount 2 stock springs. There is already a hole in the other plate, so I don't even have to take the primary apart to make a hole. I already welded the tab to align the spring and ordered a second spring..

The crazy thing is that I like not having a center stand when riding locally, but I do think it would be handy to have mounted if I got a flat tire out riding somewhere. I like having it for storing the bike or working on the bike over the winter months. Even though my preference is not to have it, I still want the option to have it on the bike when I ride it and have it not bounce off the pavement occasionally... I can't have a center stand that does that,.... no way!

Somewhat related content: The spring on my '72 was getting tired so I ordered one from one of the US based, generic Brit bike suppliers. I got it on, but when I pulled the bike up on the stand, the spring released and put a divot in my driveway. Seems that the OEM spring has a dogleg on the frame end to clear the stand pivot bolt...the replacement (came in an Andover bag) doesn't have that dogleg and fouls on the bolt. I even reversed the bolt to put the thinner head on the inside, but no joy. I looked at the spring in Andover's catalog and it doesn't appear to have the dogleg??

My main stand spring from Andover fouled the Andover supplied nut or bolt head no matter which way round I fitted it. So I made a pivot bolt with a reduced head. Also the Andover supplied bolt was all thread (top one) which isn’t the best application for a pivot.