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Front suspension question 83 R80ST

SGTBILL

SGTBILL

The Big Red One
Hello all. I have a great airhead that started life as an R80ST but has been modified somewhat. Siebenrock 1000cc cylinders, classic valve covers, dual exhaust (like /6 or /7), and old wixom bags. It runs great and I enjoy riding the back roads here in beautiful southern Indiana. When there are rough spots I can really feel the front forks "hit bottom". I am not sure whether this is just an indication of a fork oil change, better spring or what.

Any advice on how to figure this out? I am ordering supplies for annual fluid changes so if I need to do the springs now is the time.

F6B63A68-D1F2-4DDD-8060-03CB230989D0_1_105_c.jpeg
 
How many miles on the bike? Why not just do a fluid change and see if makes a difference, then consider your options. If you see a bunch of black goo come out, likely the bumpers at the bottom has disintegrated.

One thing you could do is to measure the amount of sag in the front end. You want to get about 3 inches of sag in the front end...this is from the wheel completely off the ground to when you're sitting on it with normal load. If it's more than that, you might have sacked springs. You could consider adding some PVC spacers to the top of the spring under the cap. That would increase the preload.
 
20774 said:
How many miles on the bike? Why not just do a fluid change and see if makes a difference, then consider your options. If you see a bunch of black goo come out, likely the bumpers at the bottom has disintegrated.
Click to expand...

I'll probably do just that. I have also queried the previous owner who did the rebuild about 15K miles ago to see whether there are progressive or stock springs hiding in there. I have ordered my supplies (fluid, filters, crush washers, gaskets, etc) from Beemer Boneyard. I'll see what happens with just changing the fork oil.
 
sgtbill said:
I'll probably do just that. I have also queried the previous owner who did the rebuild about 15K miles ago to see whether there are progressive or stock springs hiding in there. I have ordered my supplies (fluid, filters, crush washers, gaskets, etc) from Beemer Boneyard. I'll see what happens with just changing the fork oil.
Click to expand...

When you change the fork oil use an additional 15cc of oil over the specified amount in each fork. This will decrease the volume of air in the fork tubes above the oil. Thus on fork compression the reduced volume of air will be more greatly compressed, serving as an air spring above the oil. This reduces the tendency to bottom. You might try 10cc first but I had good luck with the additional 15cc in several bikes.
 
sgtbill,
If you have a chance to talk to the previous owner, you might ask if the front forks on your bike have been changed to something other then the stock R80st front end. Yout bike has duel disks in the front, stock R80st bikes were equipped with a single disk up front.
 
CNRed said:
sgtbill,
If you have a chance to talk to the previous owner, you might ask if the front forks on your bike have been changed to something other then the stock R80st front end. Your bike has duel disks in the front, stock R80st bikes were equipped with a single disk up front.
Click to expand...

I am able to communicate with the previous owner who made the modifications. He noted that he replaced the seals and fluid before he sold me the bike. He said progressive springs would "help". I'll ask him about the dual disks.

I have ordered springs from Ted Porter's and all the supplies needed to go ahead and replace them.

Wish me luck
 
These old Airheads had three diffrent front ends.
I have a '83 R80st that I am "freshing up" as we speak.
The front forks are not real difficult, just messy to deal with.
 
Question

Okay, I have seen a couple of threads here regarding Race tech cartridge kits. Also Brook is adding them to the bike he is rebuilding.

My question is, are they so much better than the stock system? I mean, how much better are they, a little, better best? Is it REALY worth putting them in?

The reason I am phrasing my questions as I am is because for me, I have experienced many years of upgrading my two airheads in order to perform better. Somethings I have done make huge noticeable changes, others, I wonder if I should have saved my money.

For example of one of the big upgrades, Going from the stock charging system to the 600w Omega systems on my bikes no brainer, worth the money. Now I can run all the electric clothes I want as well as auxiliary lights.

On the other hand, I can point to my experience with tires. Over the years, I have seen people praise one tire company over another, one combination of tire over another, the ins and outs of having matched tires only so on and so forth. What I have found is I cannot tell the difference in handling between the four companies I have purchased from over the years. I cannot feel or notice a difference in handling with a Dunlop on the Back and Metzler on the front. So now, I don't base my tire purchase on handling, as I don't see a difference in handling worth paying top dollar for. I base my purchase on wear, price and availability. Now, I am not writing this to interrupt this thread with a tire discussion so please don't

I am writing to ask in truth, has installing the Race tech cartridges been worth it? Do I have to be an aggressive rider to feel the difference or will I feel a difference at all? St.
 
If I bought another Airhead, I would do the RaceTech cartridge kit and springs again. I installed one on my 86 R80 which has the first version of the "Brembo" forks. It now rides very nicely over both small bumps and large while still providing more controlled damping. As I understand it, the stock forks damping is essentially the same in compression and rebound. Even with the supposedly superior Brembo style forks, the stock damping mechanism is surprisingly primitive. On a stock fork, some adjustments can be made by adding more oil and/or changing the viscosity, but increasing rebound damping will also increase compression damping which you probably would not want. The cartridge emulators allow the compression and rebound damping to be separate and the rebound damping is adjustable (not especially convenient to adjust, but I found RaceTech's recommended settings to be fine for my use). If you have ever replaced the stock rear shocks on a classic bike and been impressed with the improvement, you will probably find the improvement from the emulators to be similar. I have a Ohlins remote reservoir shock on the back and RaceTech emulators in the front. Ye Olde R80 is definitely not in the rubber pig category any more.

BTW, I had previously tried a set of progressive springs but they made the ride unpleasantly stiff. In retrospect, they may have been intended for a R80RT with a fairing still installed and my R80 have been converted to a naked bike before I bought it.

The installation was not particularly difficult to perform. When I did mine a year or two ago, I wrote up a list of things I learned and posted it here. Hopefully is is still lurking in the archives.
 
The bike I modified the most was my R100. The improvements that made the biggest difference were the shocks, the fork brace, and the SJ top triple clamp. I spent a lot of time with the forks (pre Race Tech era) and got them pretty good but no where near what my R90S after RT springs and Gold Valve Emulators. I've also experienced the difference the emulators made in a Honda Hawk 650 and SV650. In response to the question above "a whole lot better" and well worth putting them in.

I am also not a fan of progressively wound springs, regardless of who makes them. The R90S had Progressives when I got it and the straight wound springs from RT were a world better. I am not a fan of having the initially soft front dive under braking and turn very stiff over the bumps in the middle of the braking zone.

That said, it depends on how you ride. I sold my R100 when I realized I was riding it as hard as the Ducati 900 SS I had concurrently. The brakes and skinny tube tires did not perform the way serious discs and big wide radial tires did and thus did not have the safety margin. I did not ride the R90S that way but I still enjoyed the difference the RT set up made.
 
CNRed said:
sgtbill,
If you have a chance to talk to the previous owner, you might ask if the front forks on your bike have been changed to something other then the stock R80st front end. Yout bike has duel disks in the front, stock R80st bikes were equipped with a single disk up front.
Click to expand...

It’s clear visually these are original ST forks ... which did arrive with mounting tabs for additional brake. You can tell by the configuration below the axle ... which perhaps could be same on R65 but nothing else.

R80ST second only to the R80G/S are considered the most special and collectible 1980s Airheads. Clean original ones sell now for more than they did new. Too bad this one has been mutilated to this extent.
 
Race Tech Cartridge

STEVENRANKIN said:
Okay, I have seen a couple of threads here regarding Race tech cartridge kits. Also Brook is adding them to the bike he is rebuilding.

My question is, are they so much better than the stock system? I mean, how much better are they, a little, better best? Is it REALY worth putting them in?

The reason I am phrasing my questions as I am is because for me, I have experienced many years of upgrading my two airheads in order to perform better. Somethings I have done make huge noticeable changes, others, I wonder if I should have saved my money.

For example of one of the big upgrades, Going from the stock charging system to the 600w Omega systems on my bikes no brainer, worth the money. Now I can run all the electric clothes I want as well as auxiliary lights.

On the other hand, I can point to my experience with tires. Over the years, I have seen people praise one tire company over another, one combination of tire over another, the ins and outs of having matched tires only so on and so forth. What I have found is I cannot tell the difference in handling between the four companies I have purchased from over the years. I cannot feel or notice a difference in handling with a Dunlop on the Back and Metzler on the front. So now, I don't base my tire purchase on handling, as I don't see a difference in handling worth paying top dollar for. I base my purchase on wear, price and availability. Now, I am not writing this to interrupt this thread with a tire discussion so please don't

I am writing to ask in truth, has installing the Race tech cartridges been worth it? Do I have to be an aggressive rider to feel the difference or will I feel a difference at all? St.
Click to expand...
I installed them on my 73/5. Best Bang for the Buck of any upgrade I have done to this bike. I spent a lot of time and money going thru just about every fork Modification possible. Some were ok some were a waste of time and money. Race Tech cartridges made me a believer.
Gator
 
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