Topic: 78 Goldwing Forks on a 76 CB750?

[dummkauf]

I've been planning on swapping out the front forks on my CB750 Project with goldwing forks so I can get a dual disc brake setup, does anyone know if this would work?  I'd also try and get the full braking system with it as well.

http://minneapolis.craigslist.org/mcy/1026031242.html

Also, assuming this will work, what would a good price be for the parts?  I'm assuming based on the pics that the guy can't verify that the brake system won't need to be rebuilt

[Jim F]

Lots of posts on this topic
Yes it will work as I have a 75GL  front end on my 75 honda

Here are some pics

[dummkauf]

I have seen most of those threads, however my concern is about the 78GL forks on a 76CB.  Most everyone I've seen has been using a GL fork from the same year as their CB...which is also what you did.  I'm trying to find out before purchasing whether or not there's some difference between the years that would cause it to not work.

[fishhead]

The 76 CB has 6 bolt brake disc, the 78 GL has 5 bolt discs and the 78 GL has the speedo drive moved to the left hand side.
 You would need the whole front end (including wheel) for it be be a close to bolt on. You would still need to make a fork stop to keep the forks/bars from hitting the tank.
 Anything can be made to work, but an earlier 75-77 FL would be closer to a bolt on with your exsisting front wheel.
 I've put the later 78 GL wheel on the 75 GL forks and it can be done, but it was a long time ago and I dont remember the details.

[dummkauf]

The 76 CB has 6 bolt brake disc, the 78 GL has 5 bolt discs and the 78 GL has the speedo drive moved to the left hand side.
 You would need the whole front end (including wheel) for it be be a close to bolt on. You would still need to make a fork stop to keep the forks/bars from hitting the tank.
 Anything can be made to work, but an earlier 75-77 FL would be closer to a bolt on with your exsisting front wheel.
 I've put the later 78 GL wheel on the 75 GL forks and it can be done, but it was a long time ago and I dont remember the details.

Currently my bike doesn't have a brake at all on the front wheel(it was parted out before I bought it for a project, along with the gauages).  Which brings me to my next question.  Obviously the speedometer would work if I get the whole front end of the bike, but would the tach from the GL work with my engine as well?

I'm thinking I am going to see what price I could get the whole front end, rear wheel, and guages for.

[fishhead]

The 76 CB has 6 bolt brake disc, the 78 GL has 5 bolt discs and the 78 GL has the speedo drive moved to the left hand side.
 You would need the whole front end (including wheel) for it be be a close to bolt on. You would still need to make a fork stop to keep the forks/bars from hitting the tank.
 Anything can be made to work, but an earlier 75-77 FL would be closer to a bolt on with your exsisting front wheel.
 I've put the later 78 GL wheel on the 75 GL forks and it can be done, but it was a long time ago and I dont remember the details.

Currently my bike doesn't have a brake at all on the front wheel(it was parted out before I bought it for a project, along with the gauages).  Which brings me to my next question.  Obviously the speedometer would work if I get the whole front end of the bike, but would the tach from the GL work with my engine as well?

 I'm not sure. The GL tach has a fuel gauge in it. I used the CB gauges on mine. I had to cut the mounts off and move them in about and inch or so to fit the GL top tree.

I'm thinking I am going to see what price I could get the whole front end, rear wheel, and guages for.

 The rear wheel is a shaft drive and won't be a bolt on to the CB.

[Geeto67]

the thing that makes this swap a bolt on is the 75-76 trees which use the same bearing size as a cb750. I don't know if 77 is the same (I think it may be) and 1978 is not going to work. You need the 75-76 front end from the trees to the tire for it to be a bolt on dual disc setup on a cb750.

[fishhead]

http://forums.sohc4.net/index.php?topic=46084.msg484557#msg484557

 The steering stems ARE the same for the 75-77 GL and the 78-79. The only difference between them is the lower triple tree for the 78 has a wider spacing on the fork stop. The 78 changed the outer bearing diameter and the fork stops need to be spaced apart to clear the wider bearings(the frame was bigger where the bearings went as apposed to the early style). The 78-79 also came factory with tapered roller bearings, the 75-77 came with ball bearings (stock). Both stems are close to 9 5/16 inches long.
 PICS. The pictures are lacking in detail as my camera is only so accurate at close ups.

 1) 78 forks on top, 75 forks on the bottom. The sliders are different as the 78-79 has the caliper mounts closer together. The 78 has the peice of paper taped to it for identification and also has the stock tapered bearings on the stem.
 2) 78 GL steering stops (about 93mm apart)
 3) 78 lower bearing diameter (30mm)
 4) 78 upper bearing diameter (26mm)

 
 

[fishhead]

and the 75 GL fork pics.

 1) Fork stops (they are about 85mm apart)
 2) bottom bearing diameter (30mm)
 3) top bearing diameter (26mm)

  You can bolt either of the GL forks up to the CB 750 SOHC frame and you can use the tapered roller bearing kit that you have for your CB to do it. You will need to make fork stops for either GL forks.
 The 78 GL uses a 5 bolt brake disc and the speedo drive was moved to the left side of the wheel, so putting your early CB wheel with 6 bolt brake discs and right side speedo drive isnt going to be a bolt on affair on the 78 forks. Using the existing 78 GL wheel with the existing 78 GL forks, calipers and discs would work fine on the earlier K.