Prolink Fork In Early Model Frame & Steering Damper

alimey4u2 · Post by **alimey4u2** » Mon Oct 29, 2007 10:58 am

I have won a set of Prolink forks on E-Bay & intend to install on my 1980 (A) model...
Any tips or helpful hints from our learned forum ?

EMS · Post by **EMS** » Mon Oct 29, 2007 3:24 pm

Oh my, Larry

I wish I could say what I want. But this very subject triggered my expulsion from you-know-where because a former CBX club celebrity told me to "shut-up" and I did not take that too well

Let me say so much, though:
I have done Prolink-fork-into-early-CBXes - conversions before. It is an easy plug-in, provided you have the Prolink triple tree. Therein, however, lies the dilemma. Honda changed the rake form 27.5 to 29.5 degrees with the Prolink models. That means, all other things being the same, the trail would increase. Now in order to keep the same trail of 120mm, Honda also changed the "offset" of the 39mm fork bridges and brought the front wheel contact patch forward and closer to the imaginary intersection between the steering axis and the road surface. This means, when a Prolink fork is being installed in an early frame, the trail will be reduced significantly. Resulting in all advantages and disadvantages of that.
The way I rode and ride my CBXes, I found it very difficult to get used to. Actually borderline dangerous in situations. I changed back. I believe the 39mm CB1100F front end is a better choice for the early CBX.

Terry · Post by **Terry** » Mon Oct 29, 2007 3:32 pm

In re: " CBX club celebrity"

Now that right there is funny...to steal a phrase from a hillbilly comedian.

alimey4u2 · Post by **alimey4u2** » Mon Oct 29, 2007 3:33 pm

Thanks for your candour Mike, I shall certainly check & put "plan B" into operation if handling is indeed compromised....

EMS · Post by **EMS** » Mon Oct 29, 2007 3:46 pm

Terry wrote:In re: " CBX club celebrity"

Now that right there is funny...to steal a phrase from a hillbilly comedian.

Terry, a former CBX club celebrity

EMS · Post by **EMS** » Mon Oct 29, 2007 3:51 pm

alimey4u2 wrote:Thanks for your candour Mike, I shall certainly check & put "plan B" into operation if handling is indeed compromised....

Larry, I also used the Prolink front brakes, both calipers and rotors with the Prolink fork. If my memory serves me well, you have a custom brake set-up on your fine 1980. I am not sure if this will easily transfer to a Prolink fork with the Dymag wheels.

alimey4u2 · Post by **alimey4u2** » Mon Oct 29, 2007 4:11 pm

May have hangers & shims fabricated to fit if necessary Mike....

Mike Barone #123 · Post by **Mike Barone #123** » Mon Oct 29, 2007 4:58 pm

alimey4u2 wrote:I have won a set of Prolink forks on E-Bay & intend to install on my 1980 (A) model...
Any tips or helpful hints from our learned forum ?

An option to overcome the issues Mike pointed out would be to use the triple trees from an 1100f which are 39mm and can be pressed right on the CBX early model steering stem....then install the late model forks.

Now I do not know the rake/trail specs on these triple trees, but I do know how they work with stock 1100f USA fork tube lowers and Canadian 1100f uppers.....since I have had this setup for years...... and I have not noticed any problems.

Quite the improvement.

Mike

alimey4u2 · Post by **alimey4u2** » Mon Oct 29, 2007 6:42 pm

Great info Guys, Many Thanks..

daves79x · Post by **daves79x** » Mon Oct 29, 2007 9:09 pm

Mike:
Actually, I never considered the difference in the geometry. Thanks for spelling that out. I've converted a couple and never noticed anything unusual - in fact - much improved in all areas. I can say that the early model (particularly the '79) can get very scary at speed with the stock forks and sport bars and slightly worn suspension components.

Alimey:
I wouldn't hesitate to try the conversion. You will need the '80-up top steering bearing. Otherwise, it's a straight swap. If you want the Euro-style bars, you probably can find some Euro Pro-Link bars over there, or select from several mid-eighties Interceptor bars. You will also have to drill the threads out of the top bridge gauge mounts. This is because you need to use the early model bolts that also mount the top of the headlight bracket.

Dave

Chris · Post by **Chris** » Mon Oct 29, 2007 9:20 pm

daves79x wrote: Alimey:
I wouldn't hesitate to try the conversion. You will need the '80-up top steering bearing. Otherwise, it's a straight swap. If you want the Euro-style bars, you probably can find some Euro Pro-Link bars over there, or select from several mid-eighties Interceptor bars. You will also have to drill the threads out of the top bridge gauge mounts. This is because you need to use the early model bolts that also mount the top of the headlight bracket.

Dave

As Dave mentioned Larry, if you need bars to fit, I do have an extra set of Interceptor bars if you need them.

alimey4u2 · Post by **alimey4u2** » Tue Oct 30, 2007 5:00 am

Again, Thanks Guys.......

Thinking aloud here... Seeing I have an 18" front wheel, I could increase the "rake" by extending the stantions (fork tubes) in the yokes & either modify the top yoke or use a clipon arrangement to mount tubular bars ? This would give me up to a 1" extension, Haven't done the math yet...& of course I would use premium engineering to do a nice job ??

Waddya think ??

EMS · Post by **EMS** » Tue Oct 30, 2007 7:42 am

Yes, you will indeed increase the trail by sliding the tubes down in the yokes thus increasing the length between steering neck and axle.
I didn't know about the 18" wheel which - theoretically - compounds the problem to begin with.
As Dave said, many who have done the conversion did not recognize any adverse effects at all. I believe it all depends on how you ride the bike. My complaints were less straight line stability at high speeds (a very "nervous" feel around the handlebars) and a sudden tipping in tight turns at low speeds.

alimey4u2 · Post by **alimey4u2** » Tue Oct 30, 2007 8:29 am

Yes Mike, when you alerted me I thought....Hmmm I have an 18" wheel that may compound the problem even more..... Plan "B" is to use maybe all the fork tube & go with a different handlebar arrangement.... Nothing like "Capt. America" though....

Louis · Post by **Louis** » Tue Oct 30, 2007 8:34 am

Larry, I would change it in a heart beat. I run the same front end with more improvments and with a 18" dymag wheel as well on my Turbo. Also use the low bars. All I can say it is great. Never feel anything that would make me want to change anything back or to something else. Larry I would change the springs in it. You will need to add a couple washers to put the stock 79/80 front fender on and may have to make the holes a bit bigger as well on it. If you need anything just let me know. Louis

The International CBX Owners Association

Prolink Fork In Early Model Frame & Steering Damper

Prolink Fork In Early Model Frame & Steering Damper

Re: 1980 Fork upgrade...