KX Riders
Maintenance & Technical => KX500 Aluminum Frame Conversion (AFC) => Topic started by: DSPMOTO on June 03, 2013, 01:46:14 PM
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its been a couple of weeks since the crash. really dont know why this happen. i have been riding the bike for just over a year as you can see from my other posts on here. but here is my story on what i remember from the day. i was at a loretta lynn area quailifier , decided i was going to race my two stroke cause i hadn't rode in a couple weeks and the 450 would have taken the fun out of the day. Got through my first two moto's smooth. Three laps in on my 2nd moto of open prosport me and a buddy were having a good battle. came around to hit the 90ft table just like i would have on any other lap. everything was going perfect until i landed. that is all i remember. my buddy that was less than a sec behind me said that nothing went wrong. he said as soon as my wheels touched the ground i was going over the bars! the last thing that went through my head was, Oh f**k she locked up and I'm going over the bars. turns out the motor didn't lock up but i did indeed go over the bars. i was knocked out cold. guess i ended up laying there for 3 laps until i was able to convince the paramedics that i was ok just got knocked out. after i got back to the truck it took me a good hour to realize what had really happen. when they finally got my bike up off the track and brought it back to me camp thats when i i realized that all my friend were not kidding about my frame breaking in half. i got very very lucky to be able to walk away from the crash with only one scratch! the next couple days after were rough, felt like i had been hit by a truck. so now i have to start all over again. thats the most upsetting thing about it all. i had just finalized everything on the bike. o well , cant wait to build a new one! :mrgreen:
(http://i1073.photobucket.com/albums/w392/dspmoto/photo.jpg) (http://s1073.photobucket.com/user/dspmoto/media/photo.jpg.html)
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Holy smokes brother, your one lucky man...
Glad your ok.
Would it be possible to post some close up pics of your head stay area?
It might help save someones life..
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Looks like it broke at your welds on the downtube?
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ouch. good to hear your OK buddy.
Odd, check out the headstay mount, bracket welded to frame is beefy enough, but the plates used to attach head to bracket look like 3/16" alum. thin stuff. and it ISNT broken doesnt appear. thats surprising.
Like said above looks like broke the rails right below the yoke then just peeled it straight back and broke the main spars.
This is an interesting incident where it looks like the engine forces on landing didnt have much impact on the fracture, but mainly the rigidity of the chassis itself when landing.
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Did you notice any excess vibration? When we had cracks in our CR500AF, it started vibrating more than normal. Had one crack all the way around the tube just below the weld into the Y.
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bad luck...but nice to sea, that only your bike is broken and you are okay... :-)
i agree with motorrad.. the welds on the y are broken like cuttings with a saw.. :|
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Bummer :|.
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here are some more pic. I wont upload all of them since you can look at them on my photobucket. feel free to post a photo from there if you would like to discuss it. I should also add that this was my 2nd time riding the bike since I had it down to bare frame to rebuild. when it was apart there was no visual sign of anything wrong with the frame. however I did case a jump the day it broke, thinking that maybe from the shock the frame received from the case is maybe what caused it to break. @cmotodad, no there was no excess vibration,i wish there was so I wouldn't of had to go through the wreck. there was no signs at all that this was going to happen. bike rode like it always did.
(http://i1073.photobucket.com/albums/w392/dspmoto/image-19.jpg) (http://s1073.photobucket.com/user/dspmoto/media/image-19.jpg.html)
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It looks like the left downtube showed signs of failing prior to the failure, the right side looks like a fresh failure. This would be another argument for Sandblasters front head stay, had you had one it may have prevented complete failure. Welds appear to have held. I do believe that the factories use the radius tubing to prevent failures like this. Seems like an old welder told me one time that you never weld square, always radius you pieces to prevent failure.
This was a 250 so, all with 500's better look close, really close.
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I think the headstay had a crack too. Why would the stay have a crack since it is behind the break? Just a thought.
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Just curious, did you stress relief the frame after weld and then heat treat?
I wondering how many actually do?
Does Service Honda?
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after the new closer pics of the y, i have to say that the weldings still look good, but the quality of the frame-rails-aluminium seems to be to low. very thinn walls also.. :|
are the frame rails selfmade? or which one do you bought?
i love the look of the al-bikes, but there is so much to watch out in cutting and welding on it what it makes a little bit dificulter than a steel-frame-conversion. in theory aluminium needs 3x thicker walls than steel, to get the same durability which make an al-frame not as half as flexibel compared to a steelframe.
just found this frame , hope it helps to bring your bike back to live... :-)
http://www.ebay.de/itm/Kawasaki-kxf-250-kx-250-f-main-frame-A1004-/251273932896?pt=UK_Motorcycle_Parts_13&hash=item3a8117f060
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It looks like the left downtube showed signs of failing prior to the failure, the right side looks like a fresh failure. This would be another argument for Sandblasters front head stay, had you had one it may have prevented complete failure. Welds appear to have held. I do believe that the factories use the radius tubing to prevent failures like this. Seems like an old welder told me one time that you never weld square, always radius you pieces to prevent failure.
This was a 250 so, all with 500's better look close, really close.
I 100% agree with dons observations here.
Never weld square tube.. in applications like this. the corners are stress risers...
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i know the hondas use some specialty extrusions. looks like square for half of it, then a chamfered edge on the outer side.
(http://pictures.topspeed.com/IMG/crop/200812/honda-crf450r-28_600x0w.jpg)
how are you supposed to radius square tubing though? just bevel the edges? to put any kind of radius on it youre taking a lot of material off and leaving the corners thin. seems like it would help the stress point, but in turn be an issue in itself.
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There is a radius 1in sq tube avaliable. The guys on banned buy it all the time. Same wall thickness as stock CRF and radius inside and out.
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d**n that would have been nice to know :|
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it makes me want to gusset mine now to make sure it does not happen to me! :?
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It makes me think that we need to prevent the engine from rotating counter clockwise using the pivot pin as the rotation center.
Any word on if the Service bikes are having this problem?
If not, what are they doing different?
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I looked at the pictures again, and I think both were showing signs of failure, one not nearly as bad as the other. Like I said before, this is a 250, maybe there are different harmonics involved than you'd see with a 500. I recently looked at the AL framed 250 I built, didn't see any signs of immenent failure, although I'm sure the original poster felt the same.
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This is very worrying. It's seems I've just built a very expensive garage ornament! I'm getting rather afraid of using the thing now. Are the frame rails JFab supplies radiused or square?
Talking of JFab, he makes a superb head steady. I think it would be far easier to have a similar bracket made for the front which picks up on the cylinder head studs. Then just a boss welded to the down tube and job done.
No guarantee, but surely a help.
Just another thought. The rails I removed from my frame were square. No radius whatsoever. Obviously Kawasaki thought the square tube was up to the job. Therefore it's something that is being introduced during the conversion. My suspicion is the lack of heat treating. There's a few frames that have let go now in more or less the same place which appear to be due to fatigue. Until somebody can supply a definitive material/heat treatment process, failures are going to continue.
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Talking of JFab, he makes a superb head steady. I think it would be far easier to have a similar bracket made for the front which picks up on the cylinder head studs. Then just a boss welded to the down tube and job done.
No guarantee, but surely a help.
Like this?
(http://www.oem-cycle.com/forum/download/file.php?id=75)
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Bingo! What would make it a little nicer would be to have the steel compress against the aluminium. Then only an aluminium boss would need to be welded to the frame instead of that bracket. Less chance of fatigue as well. It would make it "less busy" in that area and aid getting the motor in and out prividing a little more room.
As it is, I don`t see enought clearance to get the head on if the bracket was welded to the frame as it is.
In any case, I`m going to have to do something like this before I ride mine. I`m just not going to have any piece of mind otherwise. The originator of this thread was extremely lucky to come away with just a scratch and a bruise. He must bounce well!
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There is room to remove the head.
I'll demonstrate when I'm a bit further along.
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Personally, Id still prefer the steel squeezing the ali. Do you have a computer file for the plate...
What material have you used...
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I designed one just in case they were no longer available.
But, they are still for sale:
http://www.kxriders.com/forums/index.php/topic,6447.0.html (http://www.kxriders.com/forums/index.php/topic,6447.0.html)
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@motopunk the frame rails that we made were thicker than the oem frame rails. i beleive it was 6061 that was used.
i am waiting to hear back from the guy who did all my welding/cutting/bending to get all the correct anwser for these questions.
@motorrad what kind of tubing should i have used? the oem frame rails were square so i went went the square just a little bit thicker.
@jBernard the head bracket broke in the crash from the force of the bike hitting the ground. i would have noticed if it was broke prior to the frame breaking. i think i would of had more than normal vibration going on. i can pick up on very small details to my bike with riding. i have done a lot of testing in my professional career as a racer. i aslo pay a lot of attention to my bike everytime i service it which is everytime i ride.
@don46 from the pics it does look like both rails were stressed. when i check the bike out the day after the crash the rails did not have all the black resude on the breaks. i could be wrong but that is from moveing it around on the floor of the garage. the left rail deffently broke frist thought. you can see in one of the pics that the right rail was twisting when the frame did break. to me that would mean that the left gave out first and the right side was holding on for dear life. when the guy who did all the welding and stuff came to look at the bike he didnt think that there was and pre failure prior to the break. idk, we will never know which is the worse part about it all.
@sandblaster i am not sure if the frame was heat treated or not. again waiting ot ask the welder bc i dont i dont want to answer that question wrong. im sure i will talk to him over the weekend and find all this info. please feel free to ask any other questions so i can ask him (that goes for everybody). i do like your extra head stay mount. but wouldnt that make the frame more rigid? jw wondering for when i build a new one. def going to take everybodys thoughts into consideration.
@brooksie i do bounce well, over the course of my racing career i have learned to tuck and roll. lol the only thing that happen to me in the crash was ofcousre i got knocked out, but on the way over the bar the left side of the frame caught my boot. sliced about a 3 inch slot in the side of it. hit me in the leg which gave me a really big bruse and also broke my CTI2 in half. if i didnt have that brace on my left leg would have been shattered. i do know that i was very very very lucky to be able to walk away from the crash!!
ps for everybody please dont take any of these responces the wrong way. i but my bike on here for a reason. to show everybody what happen and to help everybody out with there builds. i do not want to see that happen to anybody else and i dont think i would be able to walk away from a nother frame breaking. so lets put are heads togther so we can mack these bike bullet proof. bc these bike are just dont right awesome!!!!! :-D
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OK, so the stock bike does use a radiused tubing, I have a picture also a couple of side by side pictures of radiused versus non, they do look suttle but there is a difference
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@sandblaster i am not sure if the frame was heat treated or not. again waiting ot ask the welder bc i dont i dont want to answer that question wrong. im sure i will talk to him over the weekend and find all this info. please feel free to ask any other questions so i can ask him (that goes for everybody). i do like your extra head stay mount. but wouldnt that make the frame more rigid? jw wondering for when i build a new one. def going to take everybodys thoughts into consideration.
ps for everybody please dont take any of these responces the wrong way. i but my bike on here for a reason. to show everybody what happen and to help everybody out with there builds. i do not want to see that happen to anybody else and i dont think i would be able to walk away from a nother frame breaking. so lets put are heads togther so we can mack these bike bullet proof. bc these bike are just dont right awesome!!!!! :-D
It's hard to say if that will make the frame more rigid or not.
I don't believe so.
I guess I will have to let you know after mine has been torture tested :-D
I am very glad you posted your problem and I certainly don't take anything you have said as negative.
We are all trying to help one another so anything that can add a positive light, I'm up for it and I'm sure most others feel the same way as well.
Thanks!
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@brooksie i do bounce well, over the course of my racing career i have learned to tuck and roll. lol the only thing that happen to me in the crash was ofcousre i got knocked out, but on the way over the bar the left side of the frame caught my boot. sliced about a 3 inch slot in the side of it. hit me in the leg which gave me a really big bruse and also broke my CTI2 in half. if i didnt have that brace on my left leg would have been shattered. i do know that i was very very very lucky to be able to walk away from the crash!!
The CTI2 has a lifetime warranty. I destroyed mine, shattered the top part and broke it in half and it was repaired free of charge. Glad your ok!
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I just got a new set of custom CTI's. Great kit.
Well Don46, good info. But you've pissed me off no end! :-D
What type does JFab supply, anybody know?
My frame rails are as square as can be. I really don't know what to do with this bike now. The more I read, the more concerned I'm becoming about using it. While I'm no top flight Pro, I'm still pretty quick but don't want to have an avoidable accident. I DON"T bounce well! :-(
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Not my intent to piss you off, just offer what little knowledge I have. yours is the most catastrophic failure I have ever seen. I have seen cracks but never a frame that has snapped in half. Part of the issue is that most people aren't jumping the 500's regularly. I suspect that your frame was not heat treated after welding, and that perhaps the aluminum integrity was compromised. I wouldn't give up on your project, but I would use the radiused tubing and I would probably gusset that area, and lastly I would heat treat it. Lets be realistic, these bikes are jumped, cashed and crashed in the original form with nary a frame failure, so they are up to the task if we do it right.
In one of my other post I also mentioned the harmonics, maybe there is something with the 250 that we don't see with the 500
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i did not heat treat my KX500af because i could not find any info on it/ i.e. temperature and duration of treating, also since the engine cradle in 90% of these builds are the only part fabricated, wouldn't gusseting be just as effective however just not as visually striking? :? for that matter, how much time was on the bike since the conversion? the aluminum i used looks similar as yours :oops: we have put probably 9 hrs of testing on mine as of yesterday and i inspected after riding still no visual signs of fatigue. i might try gusseting as a fail safe at this point
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Kawasaki would of release there first kx450 in 05 if it was not for frame failure so they soughted the bugs out first ,06 was pretty good ,but i have seen a 250f ,i think broken in half ,loose engine bolts ,loose steering stem does not help either ,i saw a kx250 04 2 banger crack at the top spars ,tank and seat juntion witch i put down as loose bolts ,i saw a pro frame 97 i think had a small crack at top shock mount but that had a zillion miles and jumps on it.Now yamaha s have had many frames crack all alloy ones to ,late models as well,yz 450 comes to mind ,front downtube ,this was in mxa mag ,it was a manufacture fault ,plus the 2 stroke model i saw had a massive crack where top tube meets the side tube ,another place is down neer the footpegs.If the factorys have trouble ,imagine the poor guy trying to do these mods are having ?Extra gussit guys and correct technique and materials is needed .I remember the 1980 kxs had frame breakage in a big way ,and you could get a gassit kit to solve the promblem as well as a another frame with a different part number most likely the same frame with the gassit all ready installed maybe?The 81 kx seem to be ok.
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I do some work at a heat treating-forging facility. I spoke to the manager and with all the inserts and different types of materials (on Honda frames the castings are different materials than the rails and Y) it would be very difficult to heat treat a frame. He mentioned something about stress relieve but it could change too much of the material characteristics. Just passing along what I was told.
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After looking at the photos again,what if we plug welded solid inserts in the rails where the rails weld to the frame top and bottom? Seems like the cracks we have are always just below the welded areas.
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That would look cleaner than gusseting, however hacking it back apart to do that doesnt sound like much fun :-(
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I was thinking of anyone doing a new conversion
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thats what i say again again and again... welding aluminium frames is not as half as easy as welding steel frames..
the right heat treating is important in all cases of welding to get the perfekt stability . in case of no or wrong heat treating it will break like glass right beside the welds , where the molecular chains still not arranged properly.
the same can also happen with steel when it was not welded properly, resulting in too many stress material left and right of the weld.
with heat treating before and after the welding you will allow the molecular chains to arrange properly, to make flexible material. cause when the molecules sitting too close together, the material is too stiff at this point and breaks sometime. that's the whole secret.
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I think gusseting will just move the problem. You'll still have huge heat cycles concentrated in the weld areas, except now you'll have more welds/more heat cycles. It seems this type of failure won't show up until it fails, which is typical of cycle fatigue.
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well than what is the right answer to this? since no one seems to know the temperature and duration of the heat treating and guesseting will only move the problem then what? sh*t can the square tubing and start over with radius tubing? or even a delta box tubing~ if obtainable :?
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for that matter i will email Aj and see if he can shed any light on this matter. i.e. the heat treating process
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http://www.speedymetals.com/ps-2498-170-1-sq-6061-t6511-aluminum-extruded.aspx
this is what i used. not sure if it's all the same
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not hijacking this thread, but i wonder how hexagon tubing would work? http://www.speedymetals.com/ps-2402-53-1-x-0-hex-6061-t6511-aluminum-extruded.aspx
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you used solid 1" square rod?
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Nope, didnt notice it was solid :-(
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I e-mailed AJ at Service Honda a while ago about heat treating. He said that yes, they do heat treat their frames after welding. Also, you can have a metallurgy lab test the frame before you weld it to see what alloys the frame is made from. Knowing the alloys will help you select the proper welding rod and proper type of tubing for re-constructing the cradle. It (knowing the alloys) should also dictate how the heat treating should be done.
I know that many aluminum bicycle frames made overseas are built using alloy 7005. It wouldn't surprise me if Japanese motorcycle frames were also made with 7005.
No, I've never built an aluminum frame conversion, but I thought I'd pass along the info that I have. A broken-in-half frame is a frightful sight indeed!
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DSPMOTO~ do you know if you used .063 wall or .125 wall? i think that would make a huge difference http://www.speedymetals.com/s-194-square-tube.aspx
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Lund-in response to your heat treating question, I would refer to a book that the aws(American welding society) makes. It's pretty much the bible and tells you what heat, how long, and any procedures or precautions you need to do or take for every type of metal. My dad actually has 2, from 1997, next time I stop by his house I'll try to remember to look and I'll let you know. Sorry for bumping this post
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I don't know jack about metals but from my years online within the aluminum frame conversion community 6061 seems to be the way to go,I know that is what the mounts,head stay & swing arm spacers were made from for my old cr500 conversion and that's what most of the prefab downtubes & conversion parts are made from
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Yes, I agree that 6061 is the best choice. Air craft grade baby
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hey everybody sorry that i went mia…. i am not sure if the frame was heated treated or not. i do know the metal used was 6061. since that frame broke i have seen pics of 3 others all were 2006 frames as well as i talked to a buddy at team green and was told that they even had a few frames brake in the R&D. not sure what years they did this but i would like to think that is took place within the last4 years…… also was told they were built like mine and build like service honda does theres as well.
well since the frame braking i haven't wanted to build a mother one.. i did buy a mother steel frame kx250 and put 2012-2014 kx450 plastics on it, figured i was much safer keeping it in the steel frame. /Users/dallasgarrettedmisten/Pictures/iPhoto Library.photolibrary/Masters/2013/10/31/20131031-195239/IMG_1807.JPG
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(http://i1073.photobucket.com/albums/w392/dspmoto/IMG_1807.jpg) (http://s1073.photobucket.com/user/dspmoto/media/IMG_1807.jpg.html)
(http://i1073.photobucket.com/albums/w392/dspmoto/IMG_2059.jpg) (http://s1073.photobucket.com/user/dspmoto/media/IMG_2059.jpg.html)
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I realize this is an old thread but, I broke my 2006 frame Friday. I used 7005 alloy and heat treated it, but I think the real problem is I made my front motor mounts way too large and beefy and forced the rails after the split to be too rigid except for a small 1" section between the split and the motor mount.
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do you have any pictures of where it broke?
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Not yet, have to dig the pressure washer out and find a hose that isn't frozen to wash the thing. Everything between the cradle and the front motor mount is trashed in multiple places though. Thinking I should die pen the frame if I repair it and have my front motor mount welded as low as possible to provide room for flex.
My frames a bit more redneck than some of them I've seen here. I just moved the stock cradle up and welded new straight sections between the cradle and where the bottom rail ended its upward curve. No machined pieces.
do you have any pictures of where it broke?
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this is surprising, ive seen some pretty smart people say the lower cradle(rails) hold very little weight, and most of the rigidity is between the headstay and the swingarm bolt.
if it broke below the Y, is it right on the weld? that may indicate a bad bond between Y and new frame rails.
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(http://i57.tinypic.com/2wbu6ab.jpg)
(http://i62.tinypic.com/2akljxc.jpg)
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Angled breaks would indicate tension in AL. The straight across breaks are right past the weld beads indicates either lower strength material properties or stress concentration from the weld beads (or high shear forces). Since the left side didn't even break near the weld I would guess material properties at the actual weld were fine.
I think it's all in the motor mounts. Too stiff without enough flex in the remaining material. Bending creates tension and compression, not any appreciable shear.
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thanks for the pics. thats a real interesting break, and looks like youre right in how it broke. looks like the engine got pulled backwards and just seperated itself and the rails from the static Y.
what does your headstay look like? it almost looks like the engine tried to move back 3/4" violently, cant really see how it did that with a solid headstay mount enough for it to straight shear off like the pictures show.
who did your heat treating? not to knock them or say they had anything to do with this, just i only have 1 source so far and they are $$$.
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Because a few people had problems breaking their frame rails I wanted to be sure I understood where the transfer of energy was taking place at.
Here is a rough diagram of where the mounting points are in relation to the frame.
(http://www.oem-cycle.com/forum/download/file.php?id=72)
As you can see, when coming down hard on a jump the force is transferred in a radial motion pivoting on the 17mm swing arm pivot pin.
So, the rear head stay must be in line as much as possible with the direction of the force to prevent the engine from rotating forward and putting the frame rails under tension.
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Dude. That is not a rough diagram. A rough diagram is with pen on a paper napkin with coffee stains on it! :-D Nasty break. Must have been quite scary when it came apart. :-o
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Head stay is thick plates welded to a tube the same as the ones that broke.
The beauty of 7005 AL is that it has similair properties to 6061 but you can heat treat it yourself in your oven while cooking a pizza. It's something like 200F for 6 hours and 320f for 4 hours (Don't use those numbers without verification I'm going by memory). We had an oven at work large enough for me to do it myself.
thanks for the pics. thats a real interesting break, and looks like youre right in how it broke. looks like the engine got pulled backwards and just seperated itself and the rails from the static Y.
what does your headstay look like? it almost looks like the engine tried to move back 3/4" violently, cant really see how it did that with a solid headstay mount enough for it to straight shear off like the pictures show.
who did your heat treating? not to knock them or say they had anything to do with this, just i only have 1 source so far and they are $$$.
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I'm not so sure it wasn't torsion at the steering head. Hard to say but the angled breaks up to the center point make me suspect a beam in bending with half in compression and half in tension. I'll have to look at the rest of the frame because off the top of my head I don't know how it is braced up and where those types of forces are transmitted.
Because a few people had problems breaking their frame rails I wanted to be sure I understood where the transfer of energy was taking place at.
Here is a rough diagram of where the mounting points are in relation to the frame.
As you can see, when coming down hard on a jump the force is transferred in a radial motion pivoting on the 17mm swing arm pivot pin.
So, the rear mounts must be in line as much as possible with the direction of the force.
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Dude. That is not a rough diagram. A rough diagram is with pen on a paper napkin with coffee stains on it!
Ok, well what I meant was that it was measured with a tape measure and square, not a digital protractor and micrometer, or CMM :lol:
Anyway I think it shows why so many are breaking their frame rails as if they were under extreme tension.
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I know why.
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please do tell. i have anxiety issues so breaking frames is something i'd like to not have to worry about. :lol:
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https://www.google.com/url?sa=t&source=web&rct=j&ei=WlswU-jxN9jloASn3oCQDg&url=http://www.youtube.com/watch%3Fv%3Dm2G5bldFBPY&cd=2&ved=0CDwQtwIwAQ&usg=AFQjCNF8EIuT3QvaVccs2h86Et1pfTl1vw
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thats scary and now im more anxious.
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Steve Harvey was a handsome s.o.b. when he had a carpet on his head. :lol:
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Be nice to have this model:
(http://images.motorcycle-usa.com/PhotoGallerys/zh.jpg)
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Looks like Service Honda is using an extra gusset across AND a very beefy head stay.
(http://www.servicehonda.com/SH_HTMLsiteBU_120409/images/preowned/2008%20kx250af/rtfront.jpg)
(http://www.servicehonda.com/SH_HTMLsiteBU_120409/images/preowned/2008%20kx250af/leftengine.jpg)
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where do you see a cross gusset on the SH frame?
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It's right above the motor mount and right below the exhaust in the pictures.
where do you see a cross gusset on the SH frame?
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The first kx aluminium Frame i saw was a Spy Photo of an Kawasaki kx Prototype in 1991. Now i know why they not came out with it before 2006.
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I talked about with my brother he works 20 years in a factory for pipe connectors (Parker-Ermeto). He said there is a Laboratory for Material Control what can exactly say what kind of Material the original Material/Frame is.
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Just had my main ride stolen so I might be finally starting on my AF conversion. Anyone ever figure out a solution to the frame breakage? I have an idea that I think would do the job but would add more fabrication, welding, and weight to the project.
Hijacking sandblaster's excellent diagram, I came up with this not to scale idea. Basically a 1/4" 6061 plate, or upper and lower 1/8" plates, that would follow the cradle tubing on to the head stay but even further up to be a gusset and also extends to the rear past the end of the rails to the cast piece that connects the lower rear frame together. Would obviously have a hole(s) for access to the drain plug. Could maybe even have more holes to reduce the weight some without sacrificing strength. Critiques or suggestions?
(http://i5.photobucket.com/albums/y180/KellyLee1970/KDX250AF/frame%20lay%20out%20idea.jpg)
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If you over stress one area it results in breakage in others. The whole thing is made to flex in unison , if you can figure out no weld mounts... Hint attach to the existing tabs, take a trip to the local Honda dealer & look at the front mount on a 2014 + . The welding is the jam in the works for breakage "anealing". Testing in the works for imperical data
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So, no conclusion yet. I just don't have the time to wait any more for a solution. If anyone is interested, I have an '06 250f rolling chassis I'm ready to part with.