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Old 03-01-2020, 10:00 AM   #1
Doc_V
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Need tuning advice with RaceTech Gold Valve Emulators.

I've installed a set of RaceTech Gold Emulators on my Yamaha Roadstar 1700. Based on RaceTech's online tuning calculator, for my type of riding [aggressive, advanced rider, on twisty mountain roads and canyons] they recommended their 1.0 fork spring, 15wt fork oil, and the blue [heaviest] preload spring at 2 turns in, along with the little spacer that has four bleed holes instead of two. Unfortunately, with that setup, initial impact over bumps was too harsh; the front end would come off the ground on occasion, even at slower speeds.

I called their support line and they told me to switch from the blue preload spring to the yellow [lightest] spring at 5 turns in. While it helped some, it's still too harsh on small bumps and the front end "chatters" or skips over a series bumps rather than absorbing them, especially at speed; which can be unnerving. At the same time it dives more than I'd like under hard braking.

What I want is the opposite; compliant over small bumps and more compression damping under hard braking.

I don't know if it could be contributing to the issue, but when I first assembled the forks off the bike, after installing the emulators, I was very careful to measure the fork oil level *exactly* as they recommended. However, after removing the emulator to swap over from the blue preload springs to yellow, obviously some of the oil came out with all the components, which dropped the level quite a bit. Not wanting to go through all the trouble of removing the fork tubes from the frame, so I could stand them up straight to measure the oil level perfectly, I simply topped up the oil until it was *just* covering the washer on top of the main spring. I was more concerned with making sure both forks had the same amount of oil, vs how high. As a result, I may have an extra inch of oil over the recommended amount. When I explained this to the RaceTech specialist, he didn't seem too concerned, but I thought I'd just throw it out there.

I figure my next attempt is to back the preload off of the yellow spring from 5 turns in to 2 turns, but I don't see how that would help front end dive.

FWIW, on my previous Roadstar, I ran a set of Progressive front springs with 10wt oil [no emulators] and it handled WAY better; less dive and more compliant. I could definitely make it through the twisties faster, which is a shame considering how much extra cost and effort has gone into the RaceTech set up, and it's still not even as good as the Progressives.

So what say you? Who here has experience tuning RaceTech Emulators? I could definitely use some advice.

Your input is greatly appreciated. Thanks!

Doc_V

Last edited by Doc_V; 03-01-2020 at 10:13 PM..
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Old 04-15-2020, 03:26 PM   #2
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You can try reducing your oil level a bit.
As long as you don't end up bottoming the forks , the extra air gap should soften thing up a bit.
If that doesn't do it, try going to a lighter oil.
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Old 04-15-2020, 03:58 PM   #3
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oil level has very little impact on how the fork feels in the top 2/3rds of the stroke. an extra inch is a large change and you should change it back. however, its unlikely this is affecting your harshness issue - as long as you arent bottoming the fork.

I think u have the spring rates wrong. this page says the yellow spring is heavier than blue. that changes all your previous adjustments.
https://racetech.com/page/title/Emul...Tuning%20Guide

too much compression damping AND too little compression damping can cause the front tire to come off the ground after a bump. both situations can cause harshness in the bars. you definitely need more low-speed compression damping to slow fork dive, so add more preload to the emulator spring. but you def need to sort out which spring first.

its also kinda sounds like you need more rebound damping as well. but one thing at a time.
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Old 04-15-2020, 04:17 PM   #4
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Originally Posted by Doc_V View Post
I simply topped up the oil until it was *just* covering the washer on top of the main spring. I was more concerned with making sure both forks had the same amount of oil, vs how high. As a result, I may have an extra inch of oil over the recommended amount. When I explained this to the RaceTech specialist, he didn't seem too concerned, but I thought I'd just throw it out there.
How far in to tube is this washer?
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Old 04-15-2020, 04:40 PM   #5
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Did you measure the amount of oil you took out?
This should equal the amount you refilled with.
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Old 05-04-2020, 05:35 PM   #6
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First off, yellow spring is a heavier weight than the blue spring.
The lowspeed plate with 4 holes it likely not enough low speed compression dampening.

I am guessing you drilled out the damper rod like racetech says in the instructions?


My advise from tinking with gold valves for a few years:

Yellow spring - 2 turns in from initial contact, or blue spring 4 turns (slightly softer).
Lowspeed plate with 1 hole.
Oil height set to OEM specs with gold valve in, 15w or 20w if you are a heavy rider on a heavy bike. Oil weight is only for rebound on gold valves.

I experiemented with the lowspeed bleed plates, 1 hole all the way up to 4 holes. I found that 4 holes was far too little low speed dampening, it changes when the gold valve activates in essence.
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Old 05-17-2020, 08:10 AM   #7
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Hey, thanks for all the replies guys, better late than never I suppose... So I ended up removing a couple of the washers to lessen the preload on the main spring, I also realized I made a mistake and measured my oil with the fork tube extended, when it should have been collapsed, so I removed some of the oil and between that and less preload, the bike definitely feels better. Last thing I need to do now is change the emulator spring. Thanks again, I appreciate all the help.
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Old 05-26-2020, 07:55 AM   #8
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Originally Posted by FreeRyde View Post
First off, yellow spring is a heavier weight than the blue spring.
The lowspeed plate with 4 holes it likely not enough low speed compression dampening.

I am guessing you drilled out the damper rod like racetech says in the instructions?


My advise from tinking with gold valves for a few years:

Yellow spring - 2 turns in from initial contact, or blue spring 4 turns (slightly softer).
Lowspeed plate with 1 hole.
Oil height set to OEM specs with gold valve in, 15w or 20w if you are a heavy rider on a heavy bike. Oil weight is only for rebound on gold valves.

I experiemented with the lowspeed bleed plates, 1 hole all the way up to 4 holes. I found that 4 holes was far too little low speed dampening, it changes when the gold valve activates in essence.
UPDATE: So it turns out I already had the blue preload springs at 5 turns, [not the yellow] so I backed it off to two turns. It does feel better but after reading the RT general tuning guide, I too am beginning to think the 4 hole bleed plate is too much.

FYI everything I started with, including the four hole bleeder, it's what the RT online calculator suggested; I'm finding that calculator is not so good after all. At least not for big cruisers... I also mentioned the four hole bleeder when I called RT for help and they said it didn't matter, so take what they tell you with a grain of salt. ...I guess at the end of the day, nothing beats good'ol arduous and time consuming trial and error.
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Old 06-27-2020, 02:31 PM   #9
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Originally Posted by FreeRyde View Post
First off, yellow spring is a heavier weight than the blue spring.
The lowspeed plate with 4 holes it likely not enough low speed compression dampening.

I am guessing you drilled out the damper rod like racetech says in the instructions?


My advise from tinking with gold valves for a few years:

Yellow spring - 2 turns in from initial contact, or blue spring 4 turns (slightly softer).
Lowspeed plate with 1 hole.
Oil height set to OEM specs with gold valve in, 15w or 20w if you are a heavy rider on a heavy bike. Oil weight is only for rebound on gold valves.

I experiemented with the lowspeed bleed plates, 1 hole all the way up to 4 holes. I found that 4 holes was far too little low speed dampening, it changes when the gold valve activates in essence.
How are you closing the extra lowspeed bleed holes?
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Old 07-05-2020, 09:18 AM   #10
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Originally Posted by bobl View Post
How are you closing the extra lowspeed bleed holes?
The kit came with two separate bleeders; one with 4 holes and one with 2. They even have a single bleeder hole version; if you already bought the kit, you can call RT they'll send you one.
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Old 07-05-2020, 09:27 AM   #11
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LATEST UPDATE: After swapping the 4 hole bleeder for 2, the bike is much less harsh over "square" bumps. I suspect it's because my bike is so heavy, that even with 15w fork oil, the 4 hole bleeder was allowing too much fluid to bypass the damper. Now that I've finally addressed that I can go back and do more fine tuning.

Last edited by Doc_V; 07-05-2020 at 09:48 AM..
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Old 08-11-2020, 09:35 AM   #12
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ANOTHER UPDATE: I called RT and told them about the front end diving under braking, so they sent me the 1.2kg spring [the stiffest one they have] to swap out for the 1.1kg I had. Based on my past experience I honestly didn't expect there to be a difference between the 1.1 and 1.2, but wow, the bike *finally* feels stable again! Next step: fine tune the preload on the Gold Emulator cartridges...

Last edited by Doc_V; 08-13-2020 at 09:22 PM..
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Old 09-09-2020, 01:33 PM   #13
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I'll just chime in here with my observations:

First problem I had, was discovering that the fork tubes were slightly bent, and binding. Stiff!

Second, the spring rate was off. The bike came with dual rate 20/40 pound springs. First try was Progressive springs with a true 20/40 rate. No love. Next I cut half of the 20 pound coils off of the stock springs, and installed them at 1 inch preload. Best Yet. Spring, tension, and preload should leave at least 10mm of free drop (bike only, no rider), and about 1/3 of total travel when rider is on the bike. These are not absolute numbers. What works for you is what works for you, but you need some free drop.

As to the emulator springs, Blue=40 pounds, yellow is 64 pounds, and there is a alternate 26 pound springs. I'm using the blue at about 2 3/4 turns. Looking at the washer stack, I don't see that they provide any preload, as the spring tension is set from 0 to x number of turns.?
When making adjustments to the tension spring, 1 turn is a lot! Guessing from past experience, I would estimate 1 turn to be at least 5 or 6 clicks on a clicker equipped bike. I make experiments at 1/2 turn, and fine tune at 1/4 or less. You can also adjust only one side when looking to see if you need more or less damping.

As too the damping plate holes, I went with 4 holes, after trying 2. With the 4 hole plate, bike ignores tar strips, and "crackled" pavement. The two plate doesn't on my bike.

I found the biggest plushness by dropping the 15W oil for the original 10W. Too much rebound affects plushness. If I were setting up for canyons and track days, I would use the 15, but for knocking around on the street, 10 is far more supple. Then adjust your compressing from there with spring preload. That was the biggest difference for me. As an aside, ATF has almost the same centistokes as BelRay 10 (34 vs 33), and costs about 1/3. Works for me. As to fork oil level, my bike calls for 10 oz. I am using 12. This gives me a level of about 200mm. RT recommends 140mm. My bike gets too firm at about 180. I prefer the 12 oz. at about 200mm. I don't know your forks, but mine are old school and have a drain screw on the bottom. Easy to change oil. You can also use 50/50 10W and 15W to produce 12.5 (using the same brand of oil).
I don't take the forks off the measure level. Since the level is a matter of experiment, you only need to be consistent, not exact to the mm. If both are same using any measurement that is consistent is fine. I use a tape measure like a dip stick. For instance, I will insert the tape till the it's at the 200mm line, then subtract the wet part. Say 200mm at top of fork minus 20mm wet on the bottom = 180. Whatever works.

Lastly, I make only one change at a time, otherwise confusion sets in and it's difficult to tell what change is responsible.

Okay, I'll be quiet now.

P.S. I also run my front tire down about 10 percent (29 vs 32). That gives just a little more suppleness. Check Dave Moss on youtube on tire pressure.

Last edited by bobl; 09-09-2020 at 01:48 PM..
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