Topic: Looking for Gordon frame mod equivalent 1975 CB750f

[kingrabbit]

Hi
I want to access the valve train on my CB 750f but don’t want to pull the engine. Does anyone know who sells a kit to modify the frame? Gordon Frame Kit doesn’t seem to be available anymore.
Much appreciate any info.
Thanks
Don

[newday777]

I don't remember what the Gondon kit was like. Was it a weld in place bungs or clamp style like Frank and Scottly were making?
But Carpy's has a weld in frame kit

https://carpyscaferacers.com/shop/shop-our-store/motorcycle-parts-accessories/honda-cb500-cb550-cb750-parts-upgrades/frame-adapter-honda/

[Jerry Rxman Griffin aka MuthaF'er]

Check CycleX

[newday777]

Did you call RRRToolsolutions to see if they have the kits?

https://www.rrrtoolsolutions.com/honda-cb750-frame-kit.php

[PeWe]

Or "Frank's Weldless" clamps that forum member scottly produced for a while when Frank stopped making them.

[bustech51]

Carpys Cafe Racer in California makes a nice kit.  I have used both with no problems.

Sent from my SM-G950W using Tapatalk

[CB750R]

I used the cycle-x kit. With its tube clamp style it’s not the easiest to remove/install the frame section but it works. It was 1000% easier to install my engine!

[scottly]

Yeah, the inter-locking style of the Cycle-X parts can make it more difficult to fit than the flat Carpy style, especially if the split is vertical instead of horizontal. Do either of them provide the straps and bolts for the triangle piece? The last run of weldless kits I did a whole bunch of straps while I had the machine set up for them, and I have a bunch left over, along with the bolts and nuts.

[spotty]

didn't terry make some kits using old fork tubes split and drilled for the clamps ?

[willbird]

Or "Frank's Weldless" clamps that forum member scottly produced for a while when Frank stopped making them.

One nice thing about Frank's design is that one could use it NOW, then if later on you did a full frame up restore you could use a welded type then.

I have worked up some stuff to make my own but not actually cut my K3 frame yet.


The "keys" prevent the tension of the joint from only being handled by the bolts, but after much thinking driving to and from work and other idle cpu time I think that fit up may be really tough to weld in and have it fit nice. I was thinking about 1" round tube gussets to replce the stock bent flat steel too, but now thinking more like 3/4" flushed out to the outer tubes would be sufficient and nicer, even 1/2" may be sufficient really.

A simpler joint like this but longer like the other version is what I think I will use. There is a huge amount of "grab" in the flat surface using a 1/4" button head cap screw torqued properly so that in fact the tension IMHO is not only taken by the bolt.

[kingrabbit]

Great info friends. My CB has been sitting for two seasons cause I just don’t want the hassle of pulling that engine just to check the top end. I’m pretty sure my issue is a plugged oil gallery is starving the valves on number four. My plan is to pull the camshaft and clear the gallery. I’m being optimistic I know.
I will note the RRR page says about the Gordon kit:
NOTE: These as designed exclusively for the Honda CB750 K0 ~K8 series from 1969 ~ 1978.
My scoot’s an F. Will it still work?
I called and left a message for clarification.
I was on the CycleX page too and saw their kit. Looks good too. But I couldn’t find a video on YouTube about installing it.

[CB750R]

Can’t see why it wouldn’t work on your F, I have a 77 F2 and the frame kit I purchased from cycle-x fit the I.D. of my frame tubes.

The Cycle-x kit didn’t include tabs to re attach the “triangle” I just used some flat bar, but having the welded nuts on the backside is a nice call!

[PeWe]

Frank's kit good for an eventual future going back to stock, weld frame.
Only missing metal, the thickness of the saw blade, ca 2mm that will be a good fill for a welder.
Plus the holes in the triangle that must be an important part of the frame.

[Don R]

  My Hot Rod bike had been cut years ago and I actually used a Franks style kit to re-install the lower tubes from an F1 frame into a K1 frame. I had to re-weld on the top sections of the triangle also and then cut them in the middle for the bolt-ons.
   

[grcamna2]

Or "Frank's Weldless" clamps that forum member scottly produced for a while when Frank stopped making them.

One nice thing about Frank's design is that one could use it NOW, then if later on you did a full frame up restore you could use a welded type then.

I have worked up some stuff to make my own but not actually cut my K3 frame yet.


The "keys" prevent the tension of the joint from only being handled by the bolts, but after much thinking driving to and from work and other idle cpu time I think that fit up may be really tough to weld in and have it fit nice. I was thinking about 1" round tube gussets to replce the stock bent flat steel too, but now thinking more like 3/4" flushed out to the outer tubes would be sufficient and nicer, even 1/2" may be sufficient really.

A simpler joint like this but longer like the other version is what I think I will use. There is a huge amount of "grab" in the flat surface using a 1/4" button head cap screw torqued properly so that in fact the tension IMHO is not only taken by the bolt.

I really like the ones in the top pic,on the wooden table;they look to be designed to lock-together good and solid 

[willbird]

Or "Frank's Weldless" clamps that forum member scottly produced for a while when Frank stopped making them.

One nice thing about Frank's design is that one could use it NOW, then if later on you did a full frame up restore you could use a welded type then.

I have worked up some stuff to make my own but not actually cut my K3 frame yet.


The "keys" prevent the tension of the joint from only being handled by the bolts, but after much thinking driving to and from work and other idle cpu time I think that fit up may be really tough to weld in and have it fit nice. I was thinking about 1" round tube gussets to replce the stock bent flat steel too, but now thinking more like 3/4" flushed out to the outer tubes would be sufficient and nicer, even 1/2" may be sufficient really.

A simpler joint like this but longer like the other version is what I think I will use. There is a huge amount of "grab" in the flat surface using a 1/4" button head cap screw torqued properly so that in fact the tension IMHO is not only taken by the bolt.

I really like the ones in the top pic,on the wooden table;they look to be designed to lock-together good and solid 

I only built in .005" slop of the keys in the keyways though, hindsight has me thinking welding them in will move things enough that .005" is not enough.

Bill

[grcamna2]

Or "Frank's Weldless" clamps that forum member scottly produced for a while when Frank stopped making them.

One nice thing about Frank's design is that one could use it NOW, then if later on you did a full frame up restore you could use a welded type then.

I have worked up some stuff to make my own but not actually cut my K3 frame yet.


The "keys" prevent the tension of the joint from only being handled by the bolts, but after much thinking driving to and from work and other idle cpu time I think that fit up may be really tough to weld in and have it fit nice. I was thinking about 1" round tube gussets to replce the stock bent flat steel too, but now thinking more like 3/4" flushed out to the outer tubes would be sufficient and nicer, even 1/2" may be sufficient really.

A simpler joint like this but longer like the other version is what I think I will use. There is a huge amount of "grab" in the flat surface using a 1/4" button head cap screw torqued properly so that in fact the tension IMHO is not only taken by the bolt.

I really like the ones in the top pic,on the wooden table;they look to be designed to lock-together good and solid 

I only built in .005" slop of the keys in the keyways though, hindsight has me thinking welding them in will move things enough that .005" is not enough.

Bill

I suppose you would bolt them together tight first,then weld them?

[willbird]

Or "Frank's Weldless" clamps that forum member scottly produced for a while when Frank stopped making them.

One nice thing about Frank's design is that one could use it NOW, then if later on you did a full frame up restore you could use a welded type then.

I have worked up some stuff to make my own but not actually cut my K3 frame yet.


The "keys" prevent the tension of the joint from only being handled by the bolts, but after much thinking driving to and from work and other idle cpu time I think that fit up may be really tough to weld in and have it fit nice. I was thinking about 1" round tube gussets to replce the stock bent flat steel too, but now thinking more like 3/4" flushed out to the outer tubes would be sufficient and nicer, even 1/2" may be sufficient really.

A simpler joint like this but longer like the other version is what I think I will use. There is a huge amount of "grab" in the flat surface using a 1/4" button head cap screw torqued properly so that in fact the tension IMHO is not only taken by the bolt.

I really like the ones in the top pic,on the wooden table;they look to be designed to lock-together good and solid 

I only built in .005" slop of the keys in the keyways though, hindsight has me thinking welding them in will move things enough that .005" is not enough.

Bill

I suppose you would bolt them together tight first,then weld them?

I think things will still shrink and move though. I think if you were selling them those keys would be a real lure to buyers ;-), but I still think that the joint clamped up with a 1/4-28 bolt torqued properly is not honestly putting the bolt in shear, the ends of the joints take care of compression forces.

[Don R]

 I just looked at the cycleX splices and really like the locking shape, in my opinion are way better than the flat surfaces bolted together. I think my Gordons kid had something like that.

[PeWe]

From an earlier thread
http://forums.sohc4.net/index.php/topic,174446.msg2033750.html#msg2033750

[Finnigan]

I still have an unused kit from a member here that is still in the wrappings, I don't plan to use it and could offer it for good price

[willbird]

I just looked at the cycleX splices and really like the locking shape, in my opinion are way better than the flat surfaces bolted together. I think my Gordons kid had something like that.

I have a half hour drive to and from work so ponder on all kinds of things, the frame kit is one such thing. The area IMHO is not highly stressed enough for the "good, best, and better" options may ALL work just fine really. I'm not fond of the erector set solutions to splicing the gussets, would prefer to totally remove them and make steel tube round gussets.

Bill

[kingrabbit]

Alright just got the Cycle X kit today. Exciting! My question is where exactly do I make my cuts?

[spotty]

I think things will still shrink and move though. I think if you were selling them those keys would be a real lure to buyers ;-), but I still think that the joint clamped up with a 1/4-28 bolt torqued properly is not honestly putting the bolt in shear, the ends of the joints take care of compression forces.

One option is to weld the bungs in, but make the “tube” from solid aluminum round bar. That piece you can cut after the welding process to ensure a proper fit-up. I bolted them together during the weld process to keep the alignment perfect. After welding, the smallest amount of sanding brought the fit in perfectly.

The weight difference is neglible, the strength is massive.

thats a nice version of this , how do you fix the attach to the top tube bits ?

[scottly]

The weight difference is neglible, the strength is massive.

Just how much do those solid aluminum bars weigh?

[willbird]

The weight difference is neglible, the strength is massive.

Just how much do those solid aluminum bars weigh?

Each leg weighs less than 1#. Heavier than thin steel tube, but you’d never ride the difference.

One can get super heavy wall aluminum tube intended for suspension rods too, has an ID close to the correct size and maybe the exact tap dril size for spherical rod ends. Friend used it on a Sprint Car. That would be a .578"  ID for 5/8 rod ends. of course then it cannot be milled on the ends like a solid bar. Tying the two bars together is interesting for sure, makes things simpler. Gives me something to ponder in my drive time LOL.

I had planned on milling up a solid jig out of 1" square solid steel to hold the parts getting welded into the frame in alignment...it would need an area for RH and LH side gusset fixturing to bolt on. Thinking out loud the whole bolt in portion could maybe be plasma cut out of plate as one piece with some thought. Not sure where plasma cut drops the microphone with aluminum as far as thickness goes. Just saw a guy cut some 3/16" on a youtube channel and it looked really nice as far as cut quality goes. Quick look says it takes 300 amps to plasma cut 1" aluminum :-).

[willbird]

If you used tube aluminum, you’d still need to mill and weld the lug into it so that you could connect to the steel frame. Hence, I went with solid bar and simply milled the lug end. Super simple. Chucked the rod into a collet block, milled it, spun it 180* in the vise and pushed “repeat”. Did the same collet block milling on the steel lugs after I turned a shoulder for fit into the stock tube.

Put the steel lugs into the stock frame, bolt the aluminum bar in place, align it as needed, tack the steel lugs. Weld it out, unbolt it, massage as needed. I doubt it took me a full 2 hours from raw frame to done.

I did add some shim stick between the round bar and steel lugs when welding in the cross tie to prevent it from pulling the bars too tightly and not allowing removal.

Indeed, there are several ways to skin that cat :-).

Bill