KX Riders

Maintenance & Technical => KX500 Original => Topic started by: FastKX500 on March 15, 2004, 11:55:26 AM

Title: Cracked sub frame?
Post by: FastKX500 on March 15, 2004, 11:55:26 AM: Yea i was riding today with some friends and i was crusing down this trail and all the sudden i almost slide off the back of my bike, the bar that holds my seat on like right above the air filter cracked and broke off, there was only 1 bolt holding it on..so there was too much pressure and it cracked the other bolt and some of the metal frame right off...has this ever happened to anyone else? I dont know what to do...I guess find a good welder? I was thinking bout getin the whole frame powder coated anyway...i dunno :? I had to ride the whole way back standing up :x :evil:
Title: Cracked sub frame?
Post by: kawdude on March 15, 2004, 04:11:09 PM: Watch ebay. You can usually pick one up for under fiddy bucks.
Title: Cracked sub frame?
Post by: NastyNick on March 16, 2004, 02:57:52 AM: sounds like the subframe to me. I suppose a good welder can fix it up for you, but in my case the dfo totally hammered the subframe and I had to get a new one. OEM was like $350+ so I picked up an AC Racing subframe for $150. Works like a charm
Title: Cracked sub frame?
Post by: FastKX500 on March 16, 2004, 05:26:24 AM: yea..I didnt actually crack the subframe, I cracked where the subframe bolts on above the air filter...there was only 1 bolt in on the left side and nothing on the right, so there was 2 much stress on the left and crack the side right off... SHOULD I TAKE A PIC?
Title: Cracked sub frame?
Post by: Rick on March 16, 2004, 10:24:47 AM: I had a crack after a crash. Added a small plate to support the crack on the inside of the sub frame so it would not interfere with anything else. Welded it all up, and painted it KX green once again. Never had another problem.

I'm cheap, so would just fix it myself. However, if you have to pay a welder, it might be more cost effective to purchase a new one. Ebay is a good spot.

Rick
Title: Cracked sub frame?
Post by: Ramski on March 27, 2004, 05:37:46 PM: I had the same thing. I bought my bike used and did not discover it broke until after my first ride. It's a pretty comon break on the KX500 frame. I had my brothers help me weld it back together and also weld a gussett to prevent the same thing from happening again. Here are some before and after pics. (thank god I've gotten rid of that ugly Flo Green paint now)

(http://mediaservice.photoisland.com/auction/Mar/20043271112955961465151.jpg)

(http://mediaservice.photoisland.com/auction/Mar/20043274541357831753412.jpg)

Here is another week point of the frame. I've since welded this back and when the frame gets back from the powdercoat I will install a wood block the fits nice and tight inside that tank sadle. If the fuel tank takes a hit to the side, it'll push that sadle and break it. Once the fuel tank sits cockeyed the pipe will melt it. *Hopefully this will help prevent that.

(http://mediaservice.photoisland.com/auction/Mar/20043275370047848051994.jpg)

I don't have a picture yet of my upper pipe mount fix. I'll post as soon as I get a picture of it.

Hope the info helps.
Title: Cracked sub frame?
Post by: mikesmith on March 28, 2004, 08:07:36 AM: Thanks for the pictures,I already gusseted the subframe mount like you did,but I hadnt heard of the tank saddle breaking.Thanks for the tip!
Title: Cracked sub frame?
Post by: Rick on March 29, 2004, 04:53:16 AM: Wow, nice job on the gussets!! I usually don't keep my bikes long enough to worry about this type of break, but since I'm going to hang on to the 2002 for some time, think I'll go through this summer and gusset all the weak points.

Paul, we might want to add a how to post on gussets, focusing on where gussets need to be installed. Someone else will have to write the post, as I have never made any of these changes. I will therefore be a consumer of that post.

Ramski, how much did it cost to get the frame powder coated?

Rick
Title: Cracked sub frame?
Post by: kawdude on March 29, 2004, 01:24:17 PM: I just got done gusseting the linkage mounts, riser and lower frame. I had no idea that this area was a problem. I do the gusset but I have already painted the frame...
Title: Cracked sub frame?
Post by: Ramski on March 29, 2004, 04:05:06 PM: Well, I'm lucky enough to have two brothers that are expert welders and have all the equipment. I just stand there and watch. :) My brother just got my frame back from the powder coating and I'm going over this weekend to start putting the bike back together. I'll make sure I take pictures of all the extra welds we made. I'm not sure how much the powder coating cost, I'll find out this weekend. About the only thing I didn't do that the factory bike have is the welded case guards (I'd rather trust a good skid plate).

I'd be more than happy to try and put together a how to for gussets and so forth.
Title: Cracked sub frame?
Post by: Rick on March 30, 2004, 02:35:26 AM: Great, we'll all look forward to seeing the gusset post.

On the case guards, I built a set one time on a KX250, but didn't care for the case exposure in the middle of the guard. I could have just added some expanded steel, but like you, still like a good aluminum skid plate. My plate is from a KX250, so I had to weld over the old hole and drill a new one. This thing has been hit so many times that I it's even shaped around my bottom frame rails.

Yes sir, I'll just stay with my skid plate.

Rick
Title: Cracked sub frame?
Post by: mikesmith on March 30, 2004, 06:53:15 AM: Team Kawasaki runs the KDX style bash bars and welds a steel glide plate to the frame rails.I made a aluminum skid plate(well more a glide plate) for my 500,but I plan on doing the bash bar route some day.
Title: Cracked sub frame?
Post by: FastKX500 on April 10, 2004, 05:41:25 AM: Ramski thanks alot for that pic, im getting my frame welded today, and Im using the pic to show my friend the gussets, ill post a pic when its done, thanks..
Title: Cracked sub frame?
Post by: 99KX500twofast on April 10, 2004, 02:29:28 PM: I would like to know more about the upper pipe mount bracket repair. I just trashed my pro circuit works pipe and have purchased a FMF gnarly to replace it but discovered my upper pipe mount is gone.
Title: Cracked sub frame?
Post by: Ramski on April 10, 2004, 04:28:20 PM: I'll try and get some more pics posted of my frame. I've pretty much got the bike all back together. Just waiting on my BRP clamps, pipe and a few other small items. I did take some nice pics of the frame before putting it together and I'll post those with detail on the fixes.

I got the steel subframe the other day from True Torch Welding and it looks awesome. They even powdercoated it black with goes great with my frame color. The fit is perfect too!
Title: Cracked sub frame?
Post by: teamgreen500 on April 15, 2004, 05:52:16 PM: The KDX style frame loops work REALLY WELL!

Even when some Moron runs Head-On into you at French-Gulch!

Got the Pro-Cirguit pipe with the frame loop imprint in it to proove it!

Manny
Title: Cracked sub frame?
Post by: 99tjrockcrawler on April 27, 2004, 12:57:08 PM: I just found my subframe worn by the chain. Somehow my axle adjusters came loose and the axle slide forward a little and the chain became loose. The chain then started to where the subframe right by the chain slide just before the front sprocket.
Has this ever happened to anybody?
Do you think a welder can fill in the missing material and beef it up a little? It wore almost all the way through one side so I can almost see inside the subframe.
Title: Cracked sub frame?
Post by: mikesmith on April 27, 2004, 07:34:29 PM: Thats one of the few flaws that needs fixed.Weld up the hole and weld(most pop rivit it on) some angle aluminum there.