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advice on frame chop

DaveL

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looking at pics online i see alot of people running a new frame from near the rear tank mount location down to existing swing arm, is this a safe way to build a frame? i know you can buy the weld on tail on ebay for about 3 bills, but i am on a very tight budget and thinking this might be a decent solution.

i have started the chop and if it isnt going to be safe then i will spring for the tail, but i would prefer to build it my self. any thoughts,? DSCF7121.jpg
 
found this pic online. thinking of doing my frame like that... kind of.

konging looks pretty cool too, but not what i was looking for. DSCN0545.jpg
 
Its kind of up to you and how you want it to look but if you do it like in the picture above it kind of looks like a hack together job. If you are going to do a ridged either buy a whole frame or do a compete rear hardtail kit. Its all in your personal taste though.
 
my complaint about using a swing arm for a hard tail, is that they are much stronger then the rest of the tubing. making it flex entirely in the frame and at the welds. those swing arms don't flex. not designed to. However being thin wall tube the rest of the frame will. And for the Kong chop, it needs to be fishplated on the inside. The frame load is transmitted to a thin wall tube at an angle. NOT optimal. That rear section is part of an engineered shape and is a load carrying section, but the Kong job removes that. Those Kong frame cuts will all fail.
 
well you take a piece of flat plate steel and weld it on the inside of the pipes out of sight, and trim off excess, and I would add a cross brace too, to prevent side flex. You know if you walk up to a bridge and look at it, there is nothing you can remove and still safely use it. That frame is also a well designed load bearing unit, and this Kong Cut, while I love the look, cuts that frame strength by way more then half. In fact, I bet I could walk up to that frame and grab the rear of it and bend it by hand. And the Idea of you, and a loved one riding on a compromised frame disgusts me. I would fish plate it from the shock centers to the old backbone and down the rear supports half way.
to put it another way, the force of the load on a stock frame is transmitted forward into a pyramid of metal, look close at one and imagine how the shock load travels dead into a pyramid. Now look at a Kong cut, you will see there is no such support. in fact its entire rear unit, and all the weight, torque, and shock loads are now carried by a single piece of 40 year old tubing, held at an angle. I worked on semi tractor's for 25 yrs., I can see a failure here from a mile away.
Build Safe. Your Son may want to ride it! Or My son.
 
thanks for the explaination.... i can see the point of stresses and i'm WAY too old to be riding unsafely. i just like to explore different avenues . them Kong bikes do look badass tho, Jeff
 
you know it could be done outside of the frame and some chrome trim installed it would look pretty good I bet.
 
Fish plate? Do you mean gusset?

I haven't advertised them here, but I sell universal hardtail kits. That might be what you want. See: http://www.xs650.com/forum/showthread.php?t=6258 I mainly advertise them to the XS650 and XS400 guys, but I've sold them to people who've put them on Hondas, Suzukis, Kawasakis, etc... Check out my facebook page for customer pics: http://www.facebook.com/ChopSource/photos_stream

If you can find and bend the tube, you could use your stock axle plates and hardtail it yourself.
 
well on semi trucks we called it fish plate, gusset would work since its basically a corner being strengthend
 
Fish plate? Do you mean gusset?

I haven't advertised them here, but I sell universal hardtail kits. That might be what you want. See: http://www.xs650.com/forum/showthread.php?t=6258 I mainly advertise them to the XS650 and XS400 guys, but I've sold them to people who've put them on Hondas, Suzukis, Kawasakis, etc... Check out my facebook page for customer pics: http://www.facebook.com/ChopSource/photos_stream

If you can find and bend the tube, you could use your stock axle plates and hardtail it yourself.

Travis do ou have any pics of the kits you sell on a cb?
 
No unfortunately. It would be a lot like the XS400s though with the triple backbone. I'll be sending one out this week to a guy who's going to put it on a CB650. A few of them may have ended up on a CB750, but I don't usually see or know what they go on.
 
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