Topic: frame neck jig Q?

[Don R]

 Has anyone bought a frame neck jig that they can recommend?  I have a 750 K0 frame to un-rake and a wrecked F frame I'd like to combine with another frame. I'm thinking I'll make a frame jig that will sit on the lift but need something to duplicate the rake and location of the neck. And I don't have a lathe to make the cones.
  I remember something on ebay a while back but past experience is always a good thing to hear about. Thanks.

[dragracer]

Subscribing.  I have a KZ dragbike  frame i need to derake.

[dragracer]

Found something.

[Don R]

 That's the same one I saw on ebay. Various options of brackets are available. A chunk of 2x3 tube and we're good to go.  I need a digital protractor, I have a laser level already.

[754]

 You can always do it the old way, tack and check, then weld.. straighten if need be.
 It's easy if you don't cut neck right off, cut wedge , bend back, tack, check... etc

[cbr954]

I was just going to mention that setup.  Chop source is a great company, the owner is good guy and also has the cb750.com forum

[Don R]

 I searched for tubing clamps too, there are some interesting products.

[jgger]

Didn't use a filter, didja? 

[Don R]

Nope.
  I'm chassis jig crazy lately. I'm also looking at a two part Art Morrison chassis kit for my 69 firebird. If I do that I'll need to jig it up since the floor is already removed and the new one doesn't have the stock suspension mounts. I returned the jig we borrowed to build two funny cars and my dragster.

[Don R]

You can always do it the old way, tack and check, then weld.. straighten if need be.
 It's easy if you don't cut neck right off, cut wedge , bend back, tack, check... etc

 I have done that but worry about ending up with the neck angled one way or another. And at some point confidence in the result and ease of doing the work is worth a couple hundred investment to me. A couple junk frame with titles and a pile of parts bikes suddenly it makes sense money wise. 

[philgresty]

DOHC not SOHC but still relevant

I built the following jig to modify my 750dohc frame the same way team AHM did on the AMA superbike.
I will also be moving the neck back 1" as they did, ill make one similar to the chop source neck jig for this, except tie in above the neck into the jig also for rigidity

[Don R]

 The dimpled lightening holes are awesome. I would probably jig off of the motor mount holes too. Something above the neck jig makes sense. I had thought of setting the angle and then drilling a pin to keep it there but it might be better to keep the neck jig intact.
 A guy I went to school with Had a pair of pro built dirt track frames in his possession for a couple days. They both got jigs made off of them.

[Don R]

 I finally liberated enough 2x3 tube from the car project and mocked up the 750 jig.  I have two 1/2" thick plates the rear axle fits tight in, so tight it needs honed a little. I'm planning to start at the rear and make it a lot like what Phil built. I'll most likely tack weld it and bolt it. I'll most likely buy the neck jig.
 I have a K0 frame to repair and planned to build a Drag bike A / F combo frame with a rear disc.

[Don R]

 I tacked up the jig tonight, the only pic has a pile of junk around it. I'll get a better pic and post a link. I made a rear axle jig to start with and I'll work my way forward.

[Don R]

 I have a piece of chrome moly that's a snug fit in a stock frame neck, now I need to make something perfectly straight that swings up and down. I'm thinking a piece of 2.5 x 14" thick box tube with two sides cut out and slip fit over the 2" upright. Drill on a mill, thru bolt and plate the moly tube into the square tube somehow.
 Or just buy the one on ebay.

[calj737]

Don - you might try using a piece of aluminum extrusion. They are dead straight, there's ample clamps readily available, and using a digital angle finder, you can be very precise. McMaster sells plenty of these supplies for reasonably cheap.

[754]

Most neck fixtures use 2 cones sliding ona shaft.. for a few reasons.  Your solid tube, may have to be cut out after wielding things up.
 A lot of frame jigs only get it quite close,  then after welding,  you may need to tweak it a bit .