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Next thing to dial in on my 1978 R100S

I'm getting a front tire bounce above 75 mph and my front end is very spongy. Racetrch can set me up with their gold cartridge emulator, spring and oil for $400. The forks have to be 36mm. Are my forks 36mm? Is this a good setup for this bike?

Thanks in advance,
Ron

Hi
You will read different opinions on the Emulators. Race-tech springs are also a lot stiffer than stock and reduce your fork travel. If you ride mostly good roads that might not be a worry. Aftermarket rear shocks also have less travel than stock. I fitted their emulators with sonic springs and like the result, but setting it up right is a test of patience. I will try to find you the link to previous discussions.
Yes your forks would be 36mm

You should first try getting your front end sorted out with the stock set up. It could be steering head bearings, or bent or misaligned and or stiction, wrong preload, fork oil, worn components. Have you pulled it apart and inspected it?

Emulator thread- viewtopic.php?f=1&t=2598

Mal S7 wrote:Hi
You will read different opinions on the Emulators. Race-tech springs are also a lot stiffer than stock and reduce your fork travel. If you ride mostly good roads that might not be a worry. Aftermarket rear shocks also have less travel than stock. I fitted their emulators with sonic springs and like the result, but setting it up right is a test of patience. I will try to find you the link to previous discussions.
Yes your forks would be 36mm

You should first try getting your front end sorted out with the stock set up. It could be steering head bearings, or bent or misaligned and or stiction, wrong preload, fork oil, worn components. Have you pulled it apart and inspected it?

Emulator thread- viewtopic.php?f=1&t=2598

Good advise. No, I haven't torn them down yet. I was trying to have parts in hand beforehand, but that might not work. I'll start tearing into it. Do the springs wear out? Good thread on the emulators and Progressives

What would tire balancing and changing the front fork oil cost? Seems to me I'd try that first before dropping a bunch of cash.

Kurt in S.A.

Stock works fine..........when all is in order.
As already pointed out, try and fix what you have.
A bouncing front end is more likely to be a tyre mounting/balance issue firstly, followed by fork oil and stiction.
There is only one way to assess fork alignment,
pull the whole front end apart.
Perfectly straight fork legs, and perfectly straight triple tree are the base on which to build.

Kurt in S.A. wrote:What would tire balancing and changing the front fork oil cost? Seems to me I'd try that first before dropping a bunch of cash.

Kurt in S.A.

Again, good advise. I'm going to replace the seals next week. I'll balance the tire too. I've never noticed a difference after tire balancing before

Be sure and check the tire mold lines relative to the rim all the way around. If a tire doesn't seat correctly, it will create handling problems. It's easy to spot.

Kurt in S.A.

Good call, Kurt. Usually it's tubeless tires that have that issue, but I'm sure it could happen with a tube-type as well.

Holysmoke if your rear tyre has flattened off, that could account for half of your handling problems.

ME 109 wrote:Holysmoke if your rear tyre has flattened off, that could account for half of your handling problems.

30 Pounds front and rear. I'll Check the bead