1973 TX650 Rear Axle Problem

[1973 TX650 Chopper]

Hey everyone. Love this site! I have a 1973 TX650 custom hardtail. I bought it 80% complete and I've finished it. My problem is the rear wheel is wobbly and loose. I noticed this when I raised the rear wheel off the ground. The wheel wobbles back and forth way too much. I tried to tear the rear wheel assembly apart to inspect, but then I ran into another problem. I can't get the nut off the axle! I'm starting to wonder if the original owner made a custom rear axle. There is a small hole about 1/4 inch into the axle end where normally there would be a hole drilled all the way through so you could put a rod to keep the axle from turning while removing the nut from the opposite end. This has prevented me from keeping the axle from spinning while removing the nut. I've tried my impact gun but nothing works. I tried drilling through the axle to make it like the original versions, but I can't make a dent in the axle end.

Do you think I should get someone to weld something onto the axle so I can grip it? Drilling the hole doesn't seem to work.

Once I remove the axle then I need to figure out why the wheel is wobbly. I'm wondering if the original owner put in too small of an axle, if he made his own. I have the diagrams of the rear axle differences from this site. I also have the original 1973 axle which the nut doesn't fit the current axle. Original nut is too big leading me to believe maybe it's too small of an axle in there causing the wobble. I'm going to try and attach pictures of the wheel hub area showing the gap / difference in the wheel wobble.

What's the best way to get this axle off since I can't grip it on one end?
Any idea why the wheel would wobble if it isn't an incorrect axle?

 

[gggGary]

The axle end was drilled to use a spanner wrench to hold it.

Find or make one to hold the axle. Won't know for sure til you dis-assemble but a popular F-up is
forgetting to move part #20 from the old LH bearing to the new wheel bearing.

 

[mrtwowheel]

Who built the hard tail? Do you have instructions for the hard tail? Most of the aftermarket hardtails are built with an 8-1/2" distance between the axle plates. It takes 4 washers to space the wheel so that the axle will work. I don't see any washers/spacers being used on your axle/wheel. I would guess that without the washers you have the nut tightened to the max of the threads on the axle, this is not allowing the axle to pull all of the parts tight.

In other words, you have a castle nut tightened up to the end of threads on the axle. You need to decide or get instructions on how to add spacers so that your axle works. Bearings could have been damaged because of this.

There was a length difference in axles on the early bikes, early being shorter, looks like someone put the right length on your hard tail.

Scott

 

[XSLeo]

Do you have an old inner tube from your tires. Cut a strip about as wide as the head of the axle. Long enough to wrap all the way around. This will pad the axle so you can grip it with vise grips without damage. Then take your axle to the hard ware store and find the right size washer to just slip on the major size of the axle. They don't have to be metric, Just big enough to slip on. A lot of places sell by the pound so buy at least 6.
Slip it all back together and check chain alignment. It should run straight off the front sprocket to the rear. If not add a washer between the axle adjuster and hub. Add as many as needed to get a straight chain run.
Once you get that side done look at the other side, add enough so it all just slips in between the axle plates.
Once you find out how many you need on each side take them all out. Clean the washers well. Use JB Weld to "glue" the washers together in a stack. This way you only need to handle one spacer. instead of 3 or more washers.
You might even "Glue" them to the spacers you already have.
Leo

 

[mrtwowheel]

OK, got my head straight now. If you have 3/8" thick axle plates you will need four 1/8" thick washers/bushings. These washer/bushings go between the axle plates and the chain adjusters. Two washers on each side of the wheel, placed each side of the axle plates. If that makes everything too tight to go between the axle plates you'll have to spread/bend the axle plates apart.

This allows your axle to tighten everything and makes your adjusters look and work right.

Scott

 

[1973 TX650 Chopper]

Thanks gggGary. I'm ordering a spanner wrench (never needed one before) and trying the rubber lining trick. I've heated that thing up, PB blastered it, hit it with a hammer, and used my good quality 1/2 inch impact gun. I won't know until I take it apart but it feels like #20 could be missing based on my countless hours looking at it. Or it's a spacer issue.

Thanks mrtwhowheel (Scott). Unfortunately, I don't know where the hardtail came from. It looks like I do have real close to 8.5 inches between the two plates. The original 25mm wide spacer is gone, but there is a 28 or 29 mm custom spacer in it's place that you can see in the pictures I posted of the right side. I assumed that was made to replace the old spacer and add the correct thickness instead of using washers. There are no additional spacers on the left side other than than the factory one connected to the dust cover. Once I get the axle nut off I'll tear into it and see if I'm missing parts or need more spacers. I may need to replace the bearings after I figure out the cause.

Thanks XSLeo. I'll try the rubber trick and maybe a spanner wrench to get the axle nut off. Like I noted above there is a 28mm wide spacer on the right side but nothing on the left side. I'll investigate once I get the nut off and see if more spacers helps or if it's a bigger problem.

Original owner put the axle in backwards from the original position, but I can't imagine which side the axle nut is on would have any effect whatsoever, correct?

Thanks everyone.

 

[mrtwowheel]

Check out TC Bros instructions for their hard tail. They mention the washers but are extremely vague on how many, how thick and where to place them. They also mention the length differences in the early axles. They state that the '74 axle was a short one, this is wrong, I think the change was, '73 short, '74 on were long.

Looks like you have the right axle to use with that hard tail, you just need 1/8" washers in the right places.

Scott

 

[mrtwowheel]

No problems caused by the axle being reversed. I put my axle in backwards just because that's the way Honda did it, and I like it that way.

Scott

 

[mrtwowheel]

Do you have 3/8" axle plates? Pictures of the hard tail?

Scott

 

[5twins]

I don't think your chain adjusters are original 650 ones, they look narrower. But that's OK as long as they fit the axle plates, which they seem to. No need for the washers Scott was talking about with them. Here is a 650 one and you can clearly see it's wider. It would require washers on the axle end so it didn't get pinched together too much. Also note the hole in the axle head. I usually just stick a Phillips screwdriver through it to keep the axle from turning during axle nut removal/install .....

And speaking of the axle nut, yes, yours appears to be threaded on too much and has probably run out of threads. Here's an original and as you can see, the axle barely sticks out past the nut, maybe just a thread or two .....

If you add a couple of washers, one under the nut and one under the head, that should solve that problem. Stock axle diameter is 20mm by the way.

 

[mrtwowheel]

Still curious about the thickness of those axle plates.

Scott

 

[1973 TX650 Chopper]

Still curious about the thickness of those axle plates.

Scott

Sorry, I've been busy juggling a ton of things. The axle plates are indeed 3/8" axle plates. I'll try to post a picture of the hardtail later.

 

[1973 TX650 Chopper]

So... I want to thank everyone in this community for the assistance. It's appreciated.

There is no way this axle nut is coming off traditionally. I've tried everything I can think of and everything suggested. The axle hole isn't deep enough to put anything other than a spanner pin-style wrench in and I already broke a pin on one of those. I'm going to order a new axle from Mikes XS (anyone know if that hole is all the way through?) and I'm going to use a small cutoff wheel to cut the axle nut and then probably use a nut splitter to break the nut and damage the axle, most likely. I only wish that the axle had a nut on both ends like every other axle I've removed.

Once I finally get the axle removed (somehow) then I will see if it's a missing parts issue or if it simply needs more spacers to fill the gap and tighten everything up. Then I guess I'll be replacing the axle and probably the bearings. Thanks again.

 

[5twins]

Used axles off eBay are much cheaper than buying a new one from Mike's, but you may need to do some searching. Some folks think their used stuff is "gold" and want more than new for it, lol. You can also use a TX750 axle, same part and may be easier to find for a decent price.

 

[gggGary]

Torch that nut red hot, then get a socket on it.
Fighting a really bad axle nut I did manage to cut one off by making a few slots with a dremel cut off wheel and then chiseling it off and still reused that axle after cleaning up the threads with a thread file. You can get the deepest, most effective slots by making them at an angle to the axle centerline. I suppose this would be a good time to invest in a nut splitter. One tool I don't have (yet)

 

[XSLeo]

I use drill bits to help split nuts. Start with a very small drill bit. Drill in from the end of the nut. Try to center the drill half way between the threads on the axle and the outer edge of the nut. Drill with a bit bigger bit, Keep upping bit size till you get the hole to not quite touch the threads, It can break through to the outside of nut a but. Might want to do this on the opposite side of nut too.
Now place cold chisel in the drilled hole. A few whacks with a hammer pops the nut off. If done well no damage to the threads.
As I mentioned in my other post, check the chain alignment. You may need to add a washer to get the chain to run straight.
Leo

 

[1973 TX650 Chopper]

Well, I got mad last night after a few drinks and I just took my die grinder and a small dremel cutoff wheel and hacked the thing right off. I tried at first to be careful and not damage the threads, but I decided I've had enough with this axle so I just destroyed it. I'm going to check ebay quick, and if I don't like those I'm ordering a new one from Mikes XS. I have the original 1973 TX650 axle, but that's the shorter one so it won't work. I don't like spending money I don't have to, but on this bike I don't mind trying to get the best parts for the job.

Thanks for the advice everyone. I'm going on vacation for a while; when I get home I should have the new axle and some washers to try and get this rear wheel aligned and tightened up. Then I guess it's back to playing with the carb jetting. Thanks again.

 

[TwoManyXS1Bs]

This could be enlightening.

http://www.xs650.com/threads/any-guesses-as-to-what-caused-this.34841/

 

[1973 TX650 Chopper]

Well, gggGary you nailed it. Once I removed the rear wheel it was easy to see the left side spacer #20 was missing completely. Without that spacer/flange the axle doesn't fit the bearing and wobbles around in there causing my original problem. I guess I'm ordering that spacer (even though it's only available from one place at a high cost) and new wheel bearings to go with my new axle. Once I have all the new parts I will reassemble everything and put it all back together using the forum on here that details the rear wheel bearing install.

I may still need to add a washer or two to make sure the axle is tight and the nut is not bottoming out. I read the entire forum above related to the axle nut bottoming out, but I still am not 100% clear on the entire issue. The OP stated: "The chain adjuster would not allow the axle to come far enough through for all of the threads to engage and lock down. Like Uncle Bryan pointed out. The adjuster had to be opened up slightly to lock down properly."

I guess I'm not totally sure how the chain adjuster affected the axle or the nut. I guess when I put it all back together it may make more sense to me. Thanks for al the help. Wish me luck on the new part order and the bearing install.

 

[TwoManyXS1Bs]

...I guess I'm not totally sure how the chain adjuster affected the axle or the nut...

You'll want to examine your axle adjusters.

Early adjusters were 2 equal pieces, with holes that allowed the axle to completely slide thru. With improper spacers, there's the risk of the axle nut bottoming-out on the axle's shoulder, preventing true axle tightening.

Later adjusters were 2 different parts, a left and a right, one with a slightly smaller hole for the axle threads, against which the axle's shoulder *could* bottom-out, preventing true axle tightening.

Just a heads-up for folks with custom rear ends and mix/matching parts...