XJ650 maxim swing arm extension

Hey guys,
Got an Xj650 maxim for free(as a payment for making electrics on a bike), long story short, I will build a hardtail bobber/chopper out of it.
As some of you may know, the wheel base is quite small and so im looking for ways to extend the swingarm and the driveshaft. I have found a thread where a guy suggested of using virago 700 front fork inner tubes to give it a bit of height and increase rake.
The swing arm however is the issue... it is so short that I must lengthen it. Could not find anyone who did that yet on an xj650 so though i would ask here, maybe someone has done it.
I was thinking of taking the swing arm off, pulling the shaft out and cutting them both and extending by welding, but I would prefer to replace it altogether from another bike if that is an option.
Cheers,

 

I do not know this for sure, and I dont remember where I ran across this, but I think there is a newer Yamaha cruiser that has a longer driveshaft that will work with the XJ ujoint and final drive. I am definitely not certain on this. If I happen across this info I will pass it along. Lengthening the swing arm itself isnt terribly difficult so long as it's all straight. The driveshaft would be the troublesome part as you want it to run true and in balance. If you're going to do a hardtail, why not make an entire new back half of the frame instead of using the swing arm? A swing arm hardtail is easier but you have to gusset it properly or it will crack/break the frame from the swing arm still being able to pivot technically. I am slowing working on a similar project except it's my only ride for now and it's strutted until I can lay it up to finish it how I want. Food for thought.

 

look into the xj1100 xs1100 swing arm it has a disc set up and I think it is longer do not know if it will bolt on

 

I know of exactly one person on here who did what you want to do.

You will need to make a jig for the swingarm, and one for the driveshaft.

You had better be a damned good welder, and know how to rebalance a rotating assembly.

I don't have that thread bookmarked, but a google search should turn it up.

 

a little info
https://www.xjbikes.com/forums/threads/driveshaft-extension.44647/

shaft length info
https://xjbikes.com/forums/threads/shaft-lengths.27194/

 

more stuff
https://xjbikes.com/forums/threads/drive-shaft-extention-test-ride.45640/

https://xjbikes.com/forums/threads/extended-swingarm.6479/

 

Thanks for the info ! Perhaps I wasn't clear enough with the hard tail part. I will cut the sub frame off and extend it, which i am planning to connect to the shock contacts( i have done hard tails before but on longer bikes already). I do want to push the wheel more backwards though, about 6 to 8" (15-20 cm) .
Cheers

 

Thanks ! I will lokk into the xj1100 and xs 1100. Thanks for the threats , i dont know how i missed those, this helps a lot !

 

Thanks ! I believe XJ550H shared that particular post with me. I do not want to say that I am a great welder but also not a bad one(its part of my job). Re-balancing might be a problem so I might take it to a shop, dont want to risk hospital attendance. At the same time would love to learn how to do it.
Cheers

 

I did it years ago on a xs11. I made a jig to hold the swing arm, then cut and weld 6 inches to lengthen it. Spliced 2 drive shafts together . The whole process was not easy but I wanted to see if I could do it.

I doubt the XS or XJ11 swing arm will for your bike , they are much wider.

 

2 driveshafts is the ticket! a single joint is better. I would be very tempted to machine a lap joint before welding.

 

that's the best reason to do anything

 

The drive shafts were joined with a press fit sleeve( very thick ) that had 2 holes in the center. The center was plug welded then 2 more holes drilled at 90 deg then plug welded again. The sleeve was then turned down to about 1/8 thick to fit into the swing arm. The idea of the thick press fit sleeve was to keep the drive shafts straight when welding. It worked
It held up quite well during a test ride, I was not being east on the throttle or clutch. Wanted to see if I could break it, I did not.

 

wow ! Thanks for the idea of using the press to join the shafts !
One thing I did not understand, is the sleeve and those 4 plug welds are the only thing holding the shafts together ? Or did you grind the sleeve off and then welded both shafts completely ?

 

The sleeve held the shafts straight. The first 2 plug welds welded the shafts together. Then 2 more holes were drilled and plug welded. This get the shaft welded all the way around. Then the sleeve was turned down to fit into the swingarm housing. The ends of the drive shafts that are intp the sleeve were tapered so a weld will cover 100%

 

The sleeve is a common way of repairing driveshafts in industrial and agricultural applications. It makes for a relatively straightforward field repair.