Emulator Knock off

[dave_a]

Pulled my forks apart to determine IF an emulator meant for later 35mm forks CAN be used in my '74 TX650 34mm forks.

It appears the emulator fits the upper tube, just fine. But the TX forks flow compression oil differently than later model dampening rods. The "cap" next to emulator (in pic) does not pass oil through the rod. It is sealed at the top. Oil flows thru the disc & shim and small hole in the cap and down the rod.

There's no ringed piston/funnel on the top of the damper rod to seat the emulator and force oil down the rod on compression. (As on 35mm fork later models). Questions:
1. Anyone been here and done this?
2. Are all XS1/2 damper rods configured in similarly to TX?
3. Will a later XS damper rod fit a 34mm fork?
4. Suggestions?

 

[jetmechmarty]

How bad do you think you need these emulators? Is this a stock bike or are you going racing? If the later, I recommend fitting later forks. If you're just out enjoying a nice old stock bike, I'd call this more trouble than it's worth.

 

[GLJ]

If you're just out enjoying a nice old stock bike, I'd call this more trouble than it's worth.

If you are only ride it occasional and when you do your just going to put-put around I would agree with you. But if it's going to really be ridden. Like it's going to rallies or something you go places on why would you not want to make your suspension work better? For a lot of us these bikes are toys. We now have the time and money to spend on them.

 

[jetmechmarty]

If you are only ride it occasional and when you do your just going to put-put around I would agree with you. But if it's going to really be ridden. Like it's going to rallies or something you go places on why would you not want to make your suspension work better? For a lot of us these bikes are toys. We now have the time and money to spend on them.

I'm cool with that. One just has to answer the question for himself. My answer may or may not be different than yours. If money is of no consideration, then Traxxion or Race Tech has the answer.

 

[dave_a]

How bad do you think you need these emulators? Is this a stock bike or are you going racing? If the later, I recommend fitting later forks. If you're just out enjoying a nice old stock bike, I'd call this more trouble than it's worth.

Well Marty, I'm not racing. P'rolly one more crash away from a career ender.
I figure I need $39 emulators because the front forks are terrible. I just put stiffer springs in and took a short ride before the holidays. Better, but it still clicks and bangs.
You put the whole Racetech package in didn't you? What did Wiley tell you that made a difference? And how much better was it than OE?
BTW, over coffee this morning, I determined I needed a machined aluminum disc to seat the emulator, collect the oil, and shorten the damper rod, so I'm not preloading the spring with the added valve height.
Tough assignment for a guy with a drill press and a grinder.

 

[AUTOMAN]

My machined seat for emul's

 

[dave_a]

Automan - PM me please. I cannot contact you via this site.
dlahlers51@gmail.com

Digging into RaceTech site, they allude to a ringed adapter as part of the "kit" for this model, TX650A.
I may have just seen the tech drawing. Thanks

 

[gggGary]

Compared to the "not all that great" later forks, the early forks are pretty rude n crude.
Which prolly means it shouldn't be too hard to make them better and this thread should be a great experiment.
@AUTOMAN that's awesome!!! Was doing this this detailed on here somewhere? Where?
If not weigh in and describe the project and your opinion on the results! (please?)

 

[AUTOMAN]

Started with all stock and was ok for smooth straight line stuff.
Played with spring load to get anti-diving calmed down on heavy braking(sound familiar)
Stoppies were dangerous when the forks bottom!
More MAIN spring pre-load just ended up harsh on bumps.

I bought these EMUL knock offs and measured everything.
Placed on bike with suggested mods with a near rigid front end as a result.
I backed off the EMUL jounce spring to minimum and was still ridiculous.

This is when I started modding the EMUL.
Extra by-pass hole and enlarged a tad.
From 38lbs/in to 11/9/7lbs/in to get some EMUL jounce adjustability.
Rebound not adjustable(much)

Racetech was made for XS650 34mm forks(so I read)
I have no idea if the Knock offs are a duplicate, or a cheap half ass copy.

These are in 36mm forks.

So if you are really bored and want to take everything apart to measure, then comprehend what they do.......

 

[gggGary]

Started with all stock and was ok for smooth straight line stuff.
Played with spring load to get anti-diving calmed down on heavy braking(sound familiar)
Stoppies were dangerous when the forks bottom!
More MAIN spring pre-load just ended up harsh on bumps.

I bought these EMUL knock offs and measured everything.
Placed on bike with suggested mods with a near rigid front end as a result.
I backed off the EMUL jounce spring to minimum and was still ridiculous.

This is when I started modding the EMUL.
Extra by-pass hole and enlarged a tad.
From 38lbs/in to 11/9/7lbs/in to get some EMUL jounce adjustability.
Rebound not adjustable(much)

Racetech was made for XS650 34mm forks(so I read)
I have no idea if the Knock offs are a duplicate, or a cheap half ass copy.

These are in 36mm forks.

So if you are really bored and want to take everything apart to measure, then comprehend what they do.......

That's awesome!
please hang around and weigh in, sounds like you know what you're doing!

 

[RC4MAN]

Interesting, I have a set of 34 that I'm rebuilding for a track bike application. Like to see what you finally come up with

 

[gggGary]

Found a pretty good stash of parts including the "lost" pair of Mikes? knock off emulators.

 

[AUTOMAN]

#1
Those plastic/metal piston rings are shot-that's a given
I made my own-shown in one drawing

Cool pre-load caps

and no, I do not know what i am doing-you flatter me

 

[gggGary]

#1
Those plastic/metal piston rings are shot-that's a given
I made my own-shown in one drawing

Cool pre-load caps

and no, I do not know what i am doing-you flatter me

from the 79 on specials.
I think the set on the far right may be from a 77?

 

[AUTOMAN]

Damn, should have grabbed the front end when I bought the swingarm and borrani wheel from a '79 SP2
thanx gary

 

[dave_a]

Damn, should have grabbed the front end when I bought the swingarm and borrani wheel from a '79 SP2
thanx gary

Automan, who turned the adapters for you? Would they make more?

Also, the Racetech Goldvalves fit w/o adapters in 35mm (I think). Racetech uses an adapter and machining of the rod to adapt to 34mm.
The Taiwan versions only fit 35mm forks.
Unless I/we get creative.
You said you have 36mm. Typo?

 

[jetmechmarty]

You put the whole Racetech package in didn't you? What did Wiley tell you that made a difference? And how much better was it than OE?

I modified XS1100 Special forks. They were made by Showa rather than KYB that the XS650 has.
It has been ten years or more, but my Race Tech experience was less than stellar. I paid the price of entry and in return I got less than what you get from MikesXS. I went to Traxxion Dynamics for springs after the fact. A visit there assured me I should have gone there for the whole shebang due to their superior customer service and the fact that they sell the Race Tech valve.
My emulator experience was a fail. I had an awful time. I met Matt Wiley at Barber Motorsports Park in the pits and he saved it. He gave me the tuning guide and explained where I went wrong. He also gave me some tuning parts for my valves.
Once I accomplished the job over again with proper installation instructions, it went very well and I was happy. I can really flog that machine confidently after the fix.
Worth it? My experience was a PITA. My stock springs were weak. I don’t care for progressive springs much in the first place. The Traxxion springs are spot on. YES, the Gold Valves are better than stock. I still have 37 mm forks. After testing as advised by Grizld1, the need to add a fork brace was apparent. That helped. I was riding a Moto Guzzi at the time. The Guzzi was far superior. The XS11 is improved to the point of it’s good enough. It also got a pair of decent shocks. There is a line if diminishing returns. You have to decide for yourself where that is.

 

[AUTOMAN]

Jet, spot on.
Quite a bit of work and trial/error to get these to work better.

No way near more modern stuff, 1980's on.

cliff

p.s. damn there is a lot of interest in these!

I thought just the piston ring fix would spark interest.

 

[dave_a]

Cliff, can you tell us where to have small batch # parts made?

 

[gggGary]

length of the 35mm damper rods vs the 34mm rod?

ignore the "air gap" that's the length less the cube on the end

(BTW, you're 34mm damper rods are slightly different than mine. Yours have a provision for a plastic wiper ring (I think). From a '75?

Also the diameter of the 35mm "piston" upper end of the rod. Versus the 34mm small disc just below the pinned cap.

35mm upper damper OD

34mm upper damper OD


The fork caps 34 & 35 use the same thread but the top diameter at the o-ring is different.
35mm cap

34mm cap


the OD at the bottom of the damper where the aluminum cap slips on also differs.
35mm damper lower OD

34mm damper lower OD