Rear stand alignment

[chris.kelly]

Are the legs on the rigid frame's rear stand parallel, or are they bowed inwards about halfway along their length?

My stand was bent in two planes. I've been able to straighten it in one plane, but to straighten it in the other, I think I'm going to have to cut the cross-bar in half, straighten each leg independently, then weld the cross-bar back together.

Here's a link that shows a rear stand like mine, which looks like it's bowed in the center (to clear the exh pipe, I assume), and more on one side than the other.

http://www.vintage-motorcycle.com/image ... p?pid=3337

[nevhunter]

Being just a "U" shape you shouldn't have to cut it. Each part should be straightened (shaped to original) and then align it by twisting the tube part. I have just had a look ar 3 of them. The RHS with the spring and stop, is curved in the top portion. The left is straight. These are from single port singles. Nev

[brenton.roy]

Hi Chris, following on from Nev's answer, be very careful with how you do your repair.
They are cast iron and really difficult to weld back together in a way that will last. The cast gets brittle and will crack somewhere else. Stands are expensive.
The way I have straightened one of mine is to heat it to dull red with an oxy all over, then focus the heat on the bit you want to bend. You'll find the metal becomes very pliable and is extremely easy to bend.
Make sure you get it very hot and then make sure you cool it slowly. Do it cold and you'll likely hear a crack and have a 2 piece stand.
If it does crack, the most successful way to weld it is to use oxy and wire weld in a way that makes a big puddle that is an alloy of the cast and wire. You can then weld a seam over this (works for repairing fins too). Again, heat it all over first.
MAP gas like plumbers use might just about be hot enough for the bending part. If you don't have an oxy. it's a cheap (er) alternative.
Good luck, Brenton

[chris.kelly]

They are cast iron and really difficult to weld back together in a way that will last.

Mine's brass with a steel cross-bar, so it must be a reproduction (I didn't think Ariel would have used brass originally).

It's pretty easy to bend, which I suppose is good if you're trying to repair it but not so good if you're using it on the bike (bends too easily).

I'll have another crack at it this weekend and see if I can get it right without cutting it in half.

[brenton.roy]

Wow - never seen one made of brass. If all else fails, you could polish it up and use a prop stand!

[john.whiting]

A lot of Indian replica stuff in the past was cast of brass.A friend had an Indian replica brass footrest on his Norton,at a rally he stood up on the pegs trials fashion to show off and suddenly dropped onto the front of the seat.Brought a tear to his eye. The originals were cast malleable iron.This should never be oxy or arc welded as it reverts to a brittle cast iron.Use nickle bronze rod for a repair equal in strength to the original. Regards John.

[nevhunter]

Nickel bronze is an excellent material for butt welding most metals. The usual precautions. Don't overheat it. The bronze is as strong as the original metal. (except the chrome moly steels which should be welded with the correct rods and heat treated afterwards to achieve maximum strength). Nev

[brenton.roy]

The originals were cast malleable iron.This should never be oxy or arc welded as it reverts to a brittle cast iron.Use nickle bronze rod for a repair equal in strength to the original. Regards John.

Hi John, I'm sure you are right with this, but I have found that with a bit of care, and a lot of careful pre heating, I have been able to make welds that seem strong via wire weld with an oxy, and which so far haven't cracked. Having said that, most haven't been under a lot of stress (broken exhaust port, fins).
I did repair a rear stand this way, and so far it is holding up OK. If / when it breaks, I'll remember that you were right!
What I do (apart from pre heating) is to spend a lot of time on the initial seam. I try to get a decent sized puddle of parent metal and wire and work it around the cracked area. I basically build out from this weld. What I think (hope) is happening is that I am making an alloy of the cast and mild steel to build on, rather than just laying the wire on the cast iron.
Anyone reading this should have worked out that I'm NOT an engineer! I worked this method out via frustration at building up fins on an early LH head that was nicely ported and difficult / expensive to replace (they changed oiling systems a couple of times in the '30's). This was the only way I could get the new material to stay put.

[david.anderson]

Chris
the photo in the attachment you posted is about right for bend. are you sure your stand is brass and not aluminium bronze, which is a lot tougher material,about equivalent to stainless steel. the attached photo is of a stand I had cast in aluminium bronze which is not as yellow as brass. sorry about the picture but it is the only one I have of the stand unpainted

aluminium bronze stand

[john.whiting]

Brenton, I dont want to criticize anyone,only offer a bit of advice.After all a stand can not cause anything serious to happen.Something which I would like to bring to everyones attention,is the welding of trailer couplings.Most of us have a bike trailer,often bought from an ad in the paper,or the like.The coupling that fits the ball on the car can be bought for a few dollars at the auto accessory shop. Usually it will have cast into it,DUCTILE IRON or SG IRON or maybe DO NOT WELD, if its a cheapie rated at 1000kg,or thereabouts.How many have you seen welded around the edge?Lots because its easier than drilling two bolts holes in the drawbar.The weld looks pretty good because the material is easy to weld,and the owner will usually say"theres nothing wrong with that,its a good weld" I have seen lots of them broken,usually when the trailer is heavily loaded.Your safety chains will usually stop a runaway,but the trailer may end up under the back of the car. All I say is "Drill the holes and put in two bolts". Expensive ones with high ratings are usually steel,but should be bolted .Regards John.