Author Topic: Quick question on frame breakage  (Read 12293 times)

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Offline SS109

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Quick question on frame breakage
« on: June 08, 2015, 02:15:18 PM »
Of those that have broken their home grown AF conversion, do you ride MX only, trails only, or both and, if both, which were you riding when it broke? Thanks.
'90 KDX 200 (rebuild - DONE!) - '94 KDX 250 (soon to be a KDX250af)

Offline SS109

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Re: Quick question on frame breakage
« Reply #1 on: June 16, 2015, 12:38:00 AM »
Bueller?
'90 KDX 200 (rebuild - DONE!) - '94 KDX 250 (soon to be a KDX250af)

Offline kxpegger

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Re: Quick question on frame breakage
« Reply #2 on: June 16, 2015, 02:54:46 PM »
Mine was built by Service Honda back in 2009. I have probably close to 400 hours on the bike and hammer the snot out of it in the Nevada desert! Hasn't fallen apart yet!
North Las Vegas

"05" RMZ450, "08" KX500AF "11" KTM 450SX-F "12" KTM 250SX "15" KTM450SX-F

Offline SS109

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Re: Quick question on frame breakage
« Reply #3 on: June 18, 2015, 06:23:29 PM »
Thanks for the input but the Service Honda frames are supposedly made different from the home grown conversions hence not really relevant.

I'm really trying to find out if the failures are an MX problem or are there also guys breaking them riding/racing off road. I have an '06 KX250f rolling chassis I'm trying to decide if it's even worth trying the conversion or just selling it off. Come on, guys, 203 views and not one person who has broken their AF conversion has replied. smh
'90 KDX 200 (rebuild - DONE!) - '94 KDX 250 (soon to be a KDX250af)

Offline kxpegger

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Re: Quick question on frame breakage
« Reply #4 on: June 21, 2015, 03:11:43 PM »
Don't know why you are focused on what doesn't work rather than what does and that is somehow not relevant to what you were originally asking? I would have been more than happy to post pictures of what works as far as frame modifications that SH has made. Good luck in what ever you are trying to accomplish by failure posts versus what works. I don't get it?  
« Last Edit: June 21, 2015, 03:14:36 PM by kxpegger »
North Las Vegas

"05" RMZ450, "08" KX500AF "11" KTM 450SX-F "12" KTM 250SX "15" KTM450SX-F

Offline SS109

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Re: Quick question on frame breakage
« Reply #5 on: June 22, 2015, 04:49:09 AM »
I know how SH does their frames. I didn't ask about specific ways someone has done the their own AF conversion or where it failed physically. I asked specifically whether it failed from riding MX or off road. It's a pretty simple question I thought. The reason I have asked that particular question is due to the fact of some known catastrophic failures and I want to know the type of riding they were doing.
« Last Edit: June 22, 2015, 04:52:27 AM by SS109 »
'90 KDX 200 (rebuild - DONE!) - '94 KDX 250 (soon to be a KDX250af)

Offline cmotodad

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Re: Quick question on frame breakage
« Reply #6 on: June 22, 2015, 03:35:45 PM »
We have built a few CR500AF's. We have cracked the welds on 2. We ride them quite hard on an mx track regularly.

Offline sandblaster

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Re: Quick question on frame breakage
« Reply #7 on: June 22, 2015, 04:25:50 PM »
There was some pics here before the great crash of this site and it showed a typical breakage and it was MX
The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline sandblaster

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Re: Quick question on frame breakage
« Reply #8 on: June 22, 2015, 04:33:05 PM »
Motocross

The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline cmotodad

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Re: Quick question on frame breakage
« Reply #9 on: June 23, 2015, 04:57:12 PM »
I really think it has more to do with the vibration when mains are worn and crank not tight. JMO. The ones we broke had the same engine and it vibrated more than the one I have now.

Offline SS109

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Re: Quick question on frame breakage
« Reply #10 on: June 30, 2015, 05:45:54 PM »
I really think it has more to do with the vibration when mains are worn and crank not tight. JMO. The ones we broke had the same engine and it vibrated more than the one I have now.

Interesting. So, I guess that begs another question. Were all the failures KX500 conversions and NOT with a KX250?
'90 KDX 200 (rebuild - DONE!) - '94 KDX 250 (soon to be a KDX250af)

Offline brooksie

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Re: Quick question on frame breakage
« Reply #11 on: October 06, 2015, 12:41:09 PM »
I seem to remember a 250 conversion where the frame snapped in a big way! The rider was knocked out cold and was very lucky to come away with just bruises. I also seem to recall he had been riding the bike very hard and completing some big jumps. I think riding ability, style, aggression are factors which play a part in the longevity of a "home grown" conversion.

Offline kxpegger

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Re: Quick question on frame breakage
« Reply #12 on: October 06, 2015, 01:52:22 PM »
Motocross



That failure in my opinion is most likely caused by an improperly designed head stay mount. All of the force is being absorbed by the frame rails instead of the frame.
North Las Vegas

"05" RMZ450, "08" KX500AF "11" KTM 450SX-F "12" KTM 250SX "15" KTM450SX-F