Discussion in '610/630' started by capt42104, Dec 22, 2011.
Beautiful bike, and your rear sub-frame will NOT break!
Installed the Nomad rear rack and subframe reinforcement rails today. The install was a bitch- the reinforcements didn't line up very well- had to drill out the holes on the frame a little to make it work. Ultimately, I think it will do the job- and the price was so cheap I couldn't justify the time and run to the hardware store to fab my own. Time will tell
Geez, their plates look remarkably like mine don't they? I gave my design away freely. Dumb, right?
The thing is they don't tie the sub together very thoroughly so you would be better off making your own from 6061 bar stock.
Oh well, time will tell for sure.
I figured I'd try them for $25- and they'd make a good template if I felt I needed to fab something more substantial. I did have to open up one of the holes a little to make them fit.
So I just got my rear sub-frame back from the welders to have the reinforcement plates welded in. Hit it with some primer before painting and then I see two cracks in the support plates that hold the two thin bars along the top of the frame. Both sides are cracked. It think this supports the back of the seat. Any ideas as to whether this is caused by vibration or too much of a load while riding. I rarely carry luggage on the bike but I have a rear rack with a fuel pack on it. Prior to having it welded there were a pair of support plates bolted on similar to CJ's design. (not mine, they came with it when I purchased the bike). Last question...Is this powder coated aluminum or anodized. The person that welded in the plates said it was powder coated as his excuse for his lousy welding job. I thought maybe he didn't bother cleaning off the metal first with a wire wheel or flap wheel prior to welding it.
Those look like fatigue or vibration cracks (same thing), and it could happen without excess weight on the back of the bike. Find a really good TIG welder to fix those cracks, or add some reinforcement. Metal prep is the key to getting a good weld, especially with TIG. If you have to spend a weekend traveling to get it done, do it! Do not put it together like it is now, and I don't think you would after all the work to get this far.
The stock frame is painted, but I don't know if it is powder coated or not. I had my frame reinforced very early and have routinely carried a full load with panniers and top duffel on a tail rack with zero issues over thousands of rough miles.
you could block the crack with a 4 mm hole made with a drill where the crack ends.
then I keep an eye on the crack but it does not seem like a structural part to have to pay urgently
Yes. Drill hole, grind out one side of the crack (slightly to allow for some filler metal), then grind the other side and fill that side. I'm seriously considering adding an additional plate to either side to beef it up further. The bottom part is fixed, may as well fix the top half too. I think I have a handle on the fix, just need to find someone (better) to do the work.
Is the crack on the same location on both sides of the subframe? If so, it could have been from the aluminium expanding during welding and elongating the lower member and stressing the tin rod that ties back to the bracket that has cracked.
Yes, you're absolutely right. They are both in the same place on either side of the frame. Given the lousy job the guy did welding in the gussets that is almost certainly the case. FML!
I suspect no one has loaded a TE more than I.
I did CJ's braces as soon as I got the bike and have no cracks at all on the upper part of the frame after 12,500 miles. Those "other" braces that only go down to the muffler mounts IMO are not the way to go. Get CJ's patterns and two more footpeg mounts and do it once. I also like that you don't have to subject the frame to welding heat or uncertain outcomes.
That being said, during my recent tear-down and check up of the bike I discovered my battery box had cracked loose from the left (exhaust) side of the subframe. I had it welded by a professional this week and added two braces from side to side just under the battery box. Fingers crossed that I won't have to deal with that again. I'll get some pics.
@Dynobob... I may have missed something. What’s the deal with the two foot peg mounts? Source?
They're the U shaped metal brackets that attach the footpeg brackets to the subframe. If you've removed your rear footpeg brackets then you already have a set, if not you can order them from KTMparts.com or wherever. Part# 8000 71091
Got it! I've now got the gussets welded into that spot, so I'll have to have a look and see if I can still add those in. The clamps that I have now are holding on my rear luggage rack, so I'll have to order two more if I want to go that route.
Look here the solution by CJBrown
Got my sub-frame back and it looks much better.
Just need primer and paint. And a few hours of re-assembly...
Lesson learned? If you're having someone weld up your frame with reinforcing plates, make absolutely sure the paint is cleaned off prior to welding. The first outfit that I sent it to didn't clean off the surface and created nasty welds full of voids and slag. When I took it to a "reputable" place they advised that they could clean it (for a fee) or I could do it myself to save some money. A $25 sandblaster kit from Princess Auto (or Harbour Freight) did the job just fine.
I noticed a break in my subframe last night, so pulled it off this morning, and found another 5 cracks! Is this a record?
Think I need to lots of bracing, and yes, I was using the reinforcing brackets.
Which reinforcing brackets? The welded ones are the only way to go. I’m using the bolt on ones and don’t really trust them.