More than a few people have made comments about me playing around on my Sporty...pulling wheelies, burning out, doing powerslides etc.

Here's their chance to say "I told you so".

A few weeks ago I was at the shop, doing wheelies across the parking lot, and then some pretty good powerslides. Bummer we did not get any pics...wasn't doing it for pics...just having fun after a long day in the shop.

The next day I noticed that the rear fender had a crack in it...all the way thru and about 1.5" long.

It was not there before, I knew it had happened when I was messing around, but took awhile for Devin and I to figure out WHY it happened. The fender had been on there for over 4000 miles, lots of wheelies, lots of racing, lots of burn-outs, and some rough roads between Mississippi and Wisconsin, with no problems.

Realized that when I was doing the powerslides the swing-arm was flexing/shifting in the rubber mount. This flexing pushed the side of the fender into a protoype bracket I was testing and that sideways stress/pushing of the fender caused the failure at the weakest point-the cut-out for the belt.

Knowing that any more riding would just make the crack spider out further, we pulled the fender.

I also pulled the offending prototype bracket and threw it in the recycle bin.





Any fix was going to mess up the paint, but there was no choice. We did not know how much, but came up with a red-neck way of trying to limit the paint damage.

Looking at the two pieces to be welded in to give strength and prevent a re-occurrence.



Had to notch this one and put one curve in it, matching the curve of the fender.





The second one needed TWO curves in it to match the curves of the fender.





Ok, here comes the red-neck part. :laugh

Decided to set as much of the fender as possible in a bucket of water, then wrap the rest of the fender in a wet towel.

Also decided to do lots of tack welds on the support pieces, leaving time to cool in-between.

First up was to weld the crack. This part generated the most heat, as it was a full penetrating weld the entire length of the crack.





Next we had to clean up the weld so the support piece would fit flush.



Continued in next post....

 

Next up was tacking in the support pieces, leaving a little cooling time between each tack...and keeping the towel as wet as possible on the paint side of the fender.






Done welding and smoothing out.



In the meantime we were riding without a rear fender.



Somehow I forgot to get any pics of what the bubbled paint looked like after the welding.

But this is what it looked like after removing all the compromised paint.



We then primed it and cleared it before the next step.

Since most of the surrounding area of this part of the fender is the black tire and black frame...I picked up a roll of black "non-slip" tape to cover the area where the paint was gone.



Just got the fender re-installed today.





Took it out for a little spin... It was a short one...no helmet, gloves or jacket in 34*...after a mile I headed back.





It's all ready for some more fun riding!

 

Nice fix! And you can't even really tell where the offending crack was with that black tape.

Gotta love having the tools and know how to fix something like that yourself. That's my goal to be prepared for any (smaller) fix that my bike might need. Good work!

 

Well done Kevin. Could you just pop round and......

 

Vance & Hines makes some stiff bushings for the swing arm that may have made that not happen. You may give those a try. They are made for the XR1200.

 

Radius that cutout dude. With that sharp 90 corner it gave the perfect place for that crack to start. Even with the thick support metal on it now I bet, in time, it will crack again.

 

Agreed, here's an example of stress points from when someone realized that airplane windows should be rounded.

 

Good thinkin'. Nice job.
Just like it never happened.

 

Thanks, I actually like the look better with the black around the cut-out.

Thanks! Not sure when/if I'll ever be crossing the pond again.

Yeah, I might do that. I removed the offending prototype bracket that the fender ran into...there was only 3/32" clearance...obviously not enough if your gonna be doing powerslides.

Now I have a bit over 3/8" clearance. I don't think it will flex that much. But replacing the bushings is now on my list. I don't see myself being any easier on the bike in the future. Too much fun! Thanks for the info.

Rog and AWS, yeah, I realized that after the fact. At minimum I could of drilled a hole at the corners. Was way pre-occupied with limiting paint damage and did not think about that. We'll see how it holds up.

Thanks!

 

Nice fix Kevin. Love your paint job, good job saving it.