Advice on Upgrade of 81 GS750E forks to 82 or 84 GS750E fork

[Anonymous]

I have an 81 GS750E with the original forks (14K miles). They work OK. I am looking for advice on the following:

1. Rebuild the original forks (35mm?).

2. Replace original forks with rebuilt 82 GS750E units (35mm?) which adds anti-dive but allows re-use of original front wheel and triple trees, etc.

3. Replace original forks with rebuilt 84 GS750E units which has anti-dive but requires the use of a 16" front wheel (I believe). I don't know the mm so I don't know if the original triple trees can be reused.

Option 1 requires my bike to be out of commission for weeks.

Option 2 least down time, retains most original parts.

Option 3 Less down time, more changes from stock including changing to 16" front/17" rear rims.

I really don't want to go the fabbed GSXR route. I want to retain the original headlight/instruments and the "stock" look as much as possible.

Any suggestions would be greatly appreciated.

 

[Anonymous]

Don't have an answer, just curious why rebuilding the current forks would take weeks. Are they damaged?

 

[moto_dan]

Rebuilding your forks shouldn't take more than a few hours. Last time I did a set it took about 2 hours. IMO the antidive units were a failed experiment in the early to mid 80's, else bikes today would still have them. For what it's worth my suggestion is to rebuild your original forks.

 

[Anonymous]

I want to send them to Race-Tech for rebuilding/upgrading with all new bushings springs, seals, o-rings, etc.

Even if I was to do the work myself, I would have to take the forks off, possibly obtain specalty tools, disassemble the forks, determine which parts need replaced, order those parts from the dealer, wait at least one week for the parts to come in, hope they arrive on time and complete, order other upgrade parts from Works Performance or Race-Tech, wait for everything to arrive, reassemble, hope everything goes perfect...

I was told by the dealer that it would take at least 2 weeks to rebuild the with stock parts.

 

[oldschoolGS]

84 GS750E forks are the same size as my 83 GS750E-37mm. Don't bother with Anti-dive- this was an 80's fad that offers no real benefit. I removed and blanked off the Anti-dive units years ago as they use brake pressure to operate(ie. rob pressure from the front calipers). I would change seals and fork oil, stiffen the front springs with pre-load adjusters (mine are Lockhart), add an aftermarket fork brace (mine is a Telefix) and a set of braided steel brake lines. This makes a good solid setup without changing stock steering geometry. Ride on, Ed.

 

[moto_dan]

84 GS750E forks are the same size as my 83 GS750E-37mm. Don't bother with Anti-dive- this was an 80's fad that offers no real benefit. I removed and blanked off the Anti-dive units years ago as they use brake pressure to operate(ie. rob pressure from the front calipers). I would change seals and fork oil, stiffen the front springs with pre-load adjusters (mine are Lockhart), add an aftermarket fork brace (mine is a Telefix) and a set of braided steel brake lines. This makes a good solid setup without changing stock steering geometry. Ride on, Ed.

Ed,
Good post. Where did you get the preload adjusters? I've thought about that mod for a while.

 

[Anonymous]

The best upgrade is the 80-81 GS1100 front end which gives larger tubes(37mm) spring preload and rebound damping adjustment. But then you are into changing the triple trees also. I still have the stock front end on mine with Progressive springs and an air balance kit as well as a copy of an Ultimate Source fork brace to go on when the slushy weather is over and the garage quites flooding out. A total rebuild may not be necessary as I have 42000 plus and my bushings were still decent just needed new seals and oil. The new springs are my idea as quick riding is what I do when I'm alone and I like a firm feel.

 

[oldschoolGS]

Dan, bought them back about 15 years ago thru a parts warehouse. Don't know if Lockhart still makes them. Each has its own air valve on top and they are screw adjustable in preload. With the Anti-dive blocked off and braided steel lines, only 2 fingers are needed for max braking. I have had this bike since new and have had practically ever mod at one time or another. I see you are in NRHills, I live up in Frisco, hope to see you on the road one day. Ride On, Ed

 

[Billy Ricks]

Dan,

I've seen some on Ebay. NOS aftermarket stuff. They've been there a few times over the last couple of months. If I see another set I'll let you know.

 

[moto_dan]

Dan, bought them back about 15 years ago thru a parts warehouse. Don't know if Lockhart still makes them. Each has its own air valve on top and they are screw adjustable in preload. With the Anti-dive blocked off and braided steel lines, only 2 fingers are needed for max braking. I have had this bike since new and have had practically ever mod at one time or another. I see you are in NRHills, I live up in Frisco, hope to see you on the road one day. Ride On, Ed

I was in Frisco last Friday at a HS softball game. Small world. You know about the Spring Texas Hill country ride coming up on May 31- June 1. You don't live too far from Mark(shaftsuzuki) who lives in the Colony. Thanks for the info. See you on the rode. BTW how do you like the TL?
Dan

 

[moto_dan]

Dan,

I've seen some on Ebay. NOS aftermarket stuff. They've been there a few times over the last couple of months. If I see another set I'll let you know.

Thanks.

 

[moto_dan]

Dan,

I've seen some on Ebay. NOS aftermarket stuff. They've been there a few times over the last couple of months. If I see another set I'll let you know.

Thanks.

 

[oldschoolGS]

I have to keep my ears open for info on that ride. The TL is a blast-a real torque monster-nothing like I have ridden before being an inline-4 guy. Just put a set of Yosh RS3's race pipes on it. Sounds incredible. The bike is just now fully broken in-2500 miles-and I am still learning to appreciate what it can do. The one bad thing is that it has put my 750E project on the backburner. It needs a clutch basket, stator/rectifier, rear master cylinder and other misc. items. Plan on slowly geting it back to 100%. Is your 750 pretty stock? If not what mods? These really are great bikes. Ride On, Ed.

 

[Anonymous]

The best upgrade is the 80-81 GS1100 front end which gives larger tubes(37mm) spring preload and rebound damping adjustment. But then you are into changing the triple trees also. I still have the stock front end on mine with Progressive springs and an air balance kit as well as a copy of an Ultimate Source fork brace to go on when the slushy weather is over and the garage quites flooding out. A total rebuild may not be necessary as I have 42000 plus and my bushings were still decent just needed new seals and oil. The new springs are my idea as quick riding is what I do when I'm alone and I like a firm feel.

I assume that means that the 81 and 82 forks are 35mm?

Where did you get the air balance kit?

Any thoughts on the advantages/disadvantages of going from the 19/18 wheel combination to the 16/17?

 

[moto_dan]

I have to keep my ears open for info on that ride. The TL is a blast-a real torque monster-nothing like I have ridden before being an inline-4 guy. Just put a set of Yosh RS3's race pipes on it. Sounds incredible. The bike is just now fully broken in-2500 miles-and I am still learning to appreciate what it can do. The one bad thing is that it has put my 750E project on the backburner. It needs a clutch basket, stator/rectifier, rear master cylinder and other misc. items. Plan on slowly geting it back to 100%. Is your 750 pretty stock? If not what mods? These really are great bikes. Ride On, Ed.

Here's the discussion about the spring Texas Hill country ride http://www.thegsresources.com/_forum/viewtopic.php?t=5490
TL = torque monster...that's what I've heard. My 750 is stock except for pipe and stage 3 jet kit. Also, I probably have some of the parts you need for your project and I'd treat you right on price.
Dan

 

[Anonymous]

Hey Mark, yes the 750 tubes are 35mm. As far as I know they were like that from the first GS750 until '82 when they added antidive for that year. Things changed in 83 with a major chassis revamp and engine updating and it was a different bike after that. The air balance kit I got was from Progressive Suspension and it wasn't all that much, 20 bucks or so.

People say that a smaller front wheel gives quicker steering and the choice of rubber is greater as well. I had an 83 1100e chassis for parts a few years back and run the 1100 rims (19 and 17") and swingarm now. I have the front end still but after reading posts I'm not sure I want to use the antidive forks or if I should hunt down a front end from an 80 or 81.I guess it would be preference of the rider. I keep the 19" front because thats what I had to work with. Most new bikes use rims smaller than 19" so I guess smaller is better from a performance aspect.

 

[oldschoolGS]

Dan, very well, I will definitly keep that in mind. I picked up a complete spare motor about 6 months ago for parts and plan on using Electrix for the stator/rectifier. Mostly it needs a lot of time and elbow grease and a few misc items once I get into it. I plan on doing it right-the bottom end is currently bone stock(crank and rods) and to handle the 802cc displacement it needs full crank work and balancing in addition to the beefed up clutch. It will probably be next summer until I get it all built and streetworthy. This 802cc motor is a monster-I am guessing about 110 rear wheel horses which makes for 3rd gear power wheelies at 90 mph. In the meantime I have the TL to ride. Ride On, Ed.

 

[Billy Ricks]

oldschool,
I've got a master cylinder you can have for shipping. I have a few other bits and pieces so figure out what you need and if I have any of it I'll let you know.

 

[oldschoolGS]

Billy, I will take you up on that rear master cylinder. That will be one less thing I will have to hunt down. Its good to know you have some extras, as I know I am going to need more parts once I get my 750 completly torn down. When you get a chance, send me an email to "mustang4@swbell.net" and let me know app. shipping cost. I will send a money order in return. Thanks Again, Ed.

 

[Anonymous]

The air balance kit I got was from Progressive Suspension and it wasn't all that much, 20 bucks or so.

I have the front end still but after reading posts I'm not sure I want to use the antidive forks or if I should hunt down a front end from an 80 or 81.

I went on Progressive's site. The air balance kit looks like it will only work with forks whose air caps have a valve which comes straight up, out of the cap. My caps have a cast-in upper portion which positions the air-valve at about 45 degrees. I don't think that I can screw the Progressive adapter on to this arangement.

As to the 80-81 GS1100E forks, I have seen them in person and they look no different than the ones on my GS750. They are clear-coated aluminum, the axle in ahead of the fork tube (but not as far from the bottom as the "L" model forks) and there are no external adjustments. They do have the air caps on the top of the fork tubes. I never measured them, so they could be 37mm. However, they use the square headlight, whose cover extends up to the guage cluster. The headlight/cover is the same for both GS750E and GS1100E. The GS750E mounts this assembly to brackets which mount inboard of the fork tubes, between the tripple clamps. The fork leg slides through rubber bushings at either end of this bracket.

If the 80-81 GS1100E forks really are 37mm, I need to find this bracket and bushings to fit the 37mm forks (83GS1100E) that I just bought, so I can reuse my headlight/cover and retain a stock appearance while avoiding rigging the wiring/headlight/mounts.