Extended Swingarm Issues

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coruscantkid

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Hey all, I have a 3" extended swingarm I am putting on my Max. It was under braced and welded locally. I went to assemble it the other day and the axle is binding. Apparently during the welding, the swingarm shrank about 0.35" as compared to the stock swingarm.

I took it to a body shop friend who used a Porta Brace but the swingarm snaps back to its original shape after the brace is removed.

Suggestions?
 
oh boy. i had a very similar issue:

http://www.vmaxforum.net/showthread.php?t=14694

i'm not sure what happened but morley made it right. he might be able to offer insight.

tl;dr version is that the mounting flange on the swingarm cocked in so that across the axle there was i believe about a 3mm difference. no binding but my bearing creaked.
 
Cut the brace to release the bind and rebraze. Do you want to go to a shorter axle? You are running a three inch extended axle right? You can get it made to any length. Sell your three inch to anyone goin to a three inch and have them make you a "one off" axle.
 
Cut the brace to release the bind and rebraze. Do you want to go to a shorter axle? You are running a three inch extended axle right? You can get it made to any length. Sell your three inch to anyone goin to a three inch and have them make you a "one off" axle.

axle = driveshaft?
 
shrank in length or width. I'm guessing width as in the left side and right side are too close together causing issues installing the axle thru the wheel and diff. Hard to tell from your description.

If that is the case maybe you can spread it apart as needed, add some heat and then let it cool and hope it stays put.
 
Sorry, I am saying axle and meaning driveshaft. If it were the axle, you should be able to install the axle, then heat and over widen it and allow to cool. I was thinking the driveshaft was too short after the extension work hence the new DRIVESHAFT, not axle. Duh.
 
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We have learned by trial and error what process of welding and tweaking it takes to get the rear swingarm right. I always warn guys about doing their own work. This is one of the very few things I won't offer a lot of help on since it's one of the things we worked so hard to achieve. This is an unusual thing for me to say since I am normally the first to offer help.

I will say that we do our extension work, then straighten the arm. Then do our brace work, then straighten the arm. Straighten can be fix twisting as well as opening width. You have to overbend to account for the spring back which is normal. We had to make our own tooling to do all this with.

Sean
 
Hey all, I have a 3" extended swingarm I am putting on my Max. It was under braced and welded locally. I went to assemble it the other day and the axle is binding. Apparently during the welding, the swingarm shrank about 0.35" as compared to the stock swingarm.

I took it to a body shop friend who used a Porta Brace but the swingarm snaps back to its original shape after the brace is removed.

Suggestions?

You''ll probably need to apply a little heat to let it relax whilst be jacked apart or over jack it enough to allow for springback when the jack is released.
That's only part of the problem however. The arm could also be twisted in one or more directions which means the axle won't particularly align from the diff side to the opposite arm hole which like I say could be up/down in/out or a combo of both.
You weld shit and it moves, it always will. It pays to make a fixture before attempting to add extensions, braces an alike.
 
You''ll probably need to apply a little heat to let it relax whilst be jacked apart or over jack it enough to allow for springback when the jack is released.
That's only part of the problem however. The arm could also be twisted in one or more directions which means the axle won't particularly align from the diff side to the opposite arm hole which like I say could be up/down in/out or a combo of both.
You weld shit and it moves, it always will. It pays to make a fixture before attempting to add extensions, braces an alike.

My experience exactly when I merely braced and notched mine. Wasn't too wide or narrow, but the axle hole didn't want to line up.

Heating it up and letting it relax while pinning everything in place did the trick. Never had a problem since.

The whole things a judgement call and I agree with Sean that doing it without a proven method AND a jig will always yield some issues that may or may not be able to be solved later.

I wouldn't dream of trying to extend one myself based on the issues I had merely bracing and notching.
 
I extended, notched and braced mine myself (thankful for the advice and material Sean helped me with) and I ran into the same problem. I had everything bolted together with a spacer I made to mimic the wheel and everything torqued to spec and it still twisted on me but not terrible. When I went to install my axle I noticed that it wouldn't go in because of the way it twisted during welding so I did my best to tweak it but what ended up working was putting the axle in as far as it would go then using a floor jack on the shouldered side of the axle (brake side) and actually using the weight of the bike to align it then tapping the axle in slowly (don't knock it off the jack) until its started into the differential then lower the bike back down and finish installing it as normal. About midway through last season I snapped a driveshaft and when I swapped it and put the wheel back on everything aligned good, I'm assuming that just riding it and racing it with the vibration let everything settle back to where I originally welded it. I've got probably 6000 miles and a shitload of 1/4 mile passes on it so far and all is well.

Sent from my ADR6425LVW using Tapatalk 2
 
oh boy. i had a very similar issue:

http://www.vmaxforum.net/showthread.php?t=14694

i'm not sure what happened but morley made it right. he might be able to offer insight.
This is not about welding itself, its about engineering.
I weld a few "warped" constructions before I learned how to do it properly.

We have learned by trial and error what process of welding and tweaking it takes to get the rear swingarm right. I always warn guys about doing their own work. This is one of the very few things I won't offer a lot of help on since it's one of the things we worked so hard to achieve. This is an unusual thing for me to say since I am normally the first to offer help.

I will say that we do our extension work, then straighten the arm. Then do our brace work, then straighten the arm. Straighten can be fix twisting as well as opening width. You have to overbend to account for the spring back which is normal. We had to make our own tooling to do all this with.

Sean

Its still possible to brace the swingarm without any JIG nor straightening.
 
The better the fit up of the metal prior to welding the less movement in the parts you will have.
 
I've never seen anything that was made out of as thin gauge as the Vmax swing arm not twist or move if welded. I've seen old timers who definitely knew what they were doing using all the tried and true methods of wet rags, short weld time etc doing narrowed 9" ford or Chevy 12 bolt rear ends and it still takes a little "after tweaking" to make it perfect. The stock swing arm is around 16 gauge "Weld it and it will Bend" I don't care how good if and engineer you are.

That being said if you were smart enough to know how much and which direction it was going to move I suppose you could compensate for it before the first weld.
 
I haven't braced any stock swingarm but without using a jig i can only see it working by spot welding the whole thing before going for the real deal. Maybe a TIG can prodeuce better results due to more local heat.
 
That being said if you were smart enough to know how much and which direction it was going to move I suppose you could compensate for it before the first weld.

THIS is the key and one of the few things we will protect about our process. Sorry guys but this is one of the big things that helps us sell our products and what we have learned (sometimes painfully) through all the arms we've built.

Sean
 
THIS is the key and one of the few things we will protect about our process. Sorry guys but this is one of the big things that helps us sell our products and what we have learned (sometimes painfully) through all the arms we've built.

Sean

Yes, this is the key but also not any secret that you need to protect ;)
 
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