Race Tech Gold Valves Suspension question

[esspressolungo]

Does anyone have experiences with running RT Gold valves in their forks or shocks. I want to upgrade the suspension on my XR400R because I can't dial the suspension in. So far I changed fork oil only, on the way a set of Eibach fork spring with a much stiffer rate over stock.

I will rebuild the rear shock in the next few weeks, but my main concern is the front, riding off-road it is either too hard and I feel every bump, or too soft and I loose control over the front.

Would be nice to hear from the experts what they think about suspension and upgrades.

cheers

 

[crs]

I'm no expert but...

When you put the new springs in also change the fork oil to a heavier weight - to match things up... Eg. if 5w change to 7.5w - or maybe even 10w if the new springs are far stiffer then standard. If that feels better but the problem is it's still too hard when the forks are near to the end of their travel, try lowering the fork oil level a bit (like take 5 or 10ml out) - that will soften rebound from there.

I'm guessing it feels soft when going slower but hard when hitting bumps going faster... On my old KLX150, the standard fork springs were too soft so I swapped to stiffer ones and used heavier fork oil. That felt better but too jarring a ride when hitting bumps faster/harder, so I took 10ml out of each leg. Made it a lot better...

Don't know where you'd get your forks revalved here... You might need some special tools to fit RT Gold Valves yourself, by the looks of it.

 

[esspressolungo]

Thanks Chris, some good information on this issue, I might also consider a Scott or GPR steering damper, they guys that had 'em put on love 'em.

 

[bikesncats]

Thanks Chris, some good information on this issue, I might also consider a Scott or GPR steering damper, they guys that had 'em put on love 'em.

I don't know RT gold valves but both marzocchi and white power offer progressive valves and many can actually fit a number of forks with only minor adjustments. Progressive valves will react differently when high speed or low speed activation is in progress.

May be worth looking into...these are usually affordable parts. Ride safe

 

[crs]

Thanks Chris, some good information on this issue, I might also consider a Scott or GPR steering damper, they guys that had 'em put on love 'em.

Racetech (Race Tech Suspension - where I guess you're getting the springs from?) - have loads of good info to help on their website...

Check the FAQ section - they explain stuff about oil viscosity and level and have links to help you find the right springs, viscosity and level to suit you and your bike.

 

[alexuk]

A few years ago now, but I put RaceTech valves in my KTM250exc, it definitely helped smooth things out when hitting large roots etc.

i dont believe you should just put a thicker oil in with heavier springs, it may be a good idea to go one grade thicker(or thinner) but not just because of the springs. Isn't there more chance of spiking with a heavier oil? Plus it will be slower

 

[crs]

i dont believe you should just put a thicker oil in with heavier springs, it may be a good idea to go one grade thicker(or thinner) but not just because of the springs. Isn't there more chance of spiking with a heavier oil? Plus it will be slower

When you change the spring rate you normally need to change the damping rate to match. (Something like proportionately - so could be a little, could be a lot.) Changing the oil viscosity changes the damping - both the compression and the rebound - BUT this can be done in various other ways too... (I've just ordered some heavier springs for the KDX - the specialist shop I ordered them from said to change from 5w to 7.5w fork oil.)

From Rudi's description it sounds like the damping is too soft for slow speed/softer impacts (first part of fork travel) and too hard for fast speed/harder impacts (last part of fork travel). Oil viscosity changes slow speed /softer impacts damping most - so increasing this should probably help Rudi. Oil level only alters damping for the last part of fork travel (faster speed/harder impacts) so lowering the level a bit could help Rudi too - if, after changing springs and fork oil, it still seems hard when the fork is near the end of its travel.

Reshimming would probably be best but that might be more complicated - depends how far you want to go... Like I said, I'm no expert - I realise tuning suspension is a fine art and others will be able to say what needs doing far more knowledgably then me. If there was a local suspension tuner, I'd say take it there (but I dont know of one), or check with one elsewhere - like Racetech.

Note, I'm paraphrasing from the KDX manual, Racetech's FAQ and from here - which is a good read: ReStackor Users Manual.

 

[esspressolungo]

Thanks for all the input I am getting here...you guys rock!!! I ordered Eibach fork springs, they are a little shorter then stock and will require a spacer from a piece of pvc tubing or aluminum. I also read about the shim stack mod, some guys at TT forum talk about taking out a few shims and get very good results with that. I will try to do that too. I choose Eibach because Eibach is the supplier for the RT springs, I had very good results on my XR250 with that brand, it transformed the bike handling by 90%. I think I will wait for the springs to arrive and then will give everything to my mechanic and him decide what to do. The 400 is so much more powerful then the XR250 so the handling is very important, harder springs on my XR600R also helped the high speed handling. Will let you know how things work.

 

[esspressolungo]

Went for the first test ride with the new Eibach spring, what a difference, everything seems to be more balanced now, this is a great upgrade for a heavy rider, not necessary if your weight is somewhere around 70-80kg, my 130 kg without gear make all the difference, I think suspension-wise I am going in the right direction. I love the 400, nice power and very high sitting position, now I can fly over everything, I think I don't need the RT gold valves anymore

 

[LivinLOS]

I keep meaning to order the racetech spring for my DRZ..

Had 2 shipito packages and forgot to order and consolidate them both times.. Its on the list.

 

[esspressolungo]

Race Tech supply is Eibach, it's the same at the end, maybe some pricing differences, I am very happy with Eibach products, had the rear shock spring from Eibach on my XR250 and now the fork springs with 47kg rate, top product

 

[hockeyrick]

I'm no expert but...

When you put the new springs in also change the fork oil to a heavier weight - to match things up... Eg. if 5w change to 7.5w - or maybe even 10w if the new springs are far stiffer then standard. If that feels better but the problem is it's still too hard when the forks are near to the end of their travel, try lowering the fork oil level a bit (like take 5 or 10ml out) - that will soften rebound from there.

I'm guessing it feels soft when going slower but hard when hitting bumps going faster... On my old KLX150, the standard fork springs were too soft so I swapped to stiffer ones and used heavier fork oil. That felt better but too jarring a ride when hitting bumps faster/harder, so I took 10ml out of each leg. Made it a lot better...

Don't know where you'd get your forks revalved here... You might need some special tools to fit RT Gold Valves yourself, by the looks of it.

Just a slight disagreement, general consensus is lighter oil is better, not heavier. Heavier oil you may get hydraulic lock or just slower damping action. There is a ton of research out, check it out for yourself! I have a crf, coz of being here in Thai RT is great but wanted to upgrade myself and they dont use progressive springs(not sure why), which I feel and have researched are a great way to go.
I added an EPM progressive spring for my weight and expertise, changed the oil, I added air valves like the old style forks to take a bit of sag and preload-just a personal preference. I think I am going to add the gold valves on the dampner side. But they handle ok as they are. The rear shock is stoch but again added an EPM progressive spring for my weight, and it did make it better, now, as good as a completely new show(RT, YSS, Ohlins)? Probably now but then cost a lot less. I dont race anymore, so dropping almost a Grand on a shock to me was not cost effective.
Anyway, thats what I did, again all mods are personal, depends on ur riding, bankbook, etc.
Ask a Q if interested!

 

[LivinLOS]

Like the dual cans.. You have them made locally ??

 

[hockeyrick]

Ben740, on FB, nan/lampang area, been around for some time

 

[bsacbob]

He's actually in Sakon Nakhon now, just got a single from him, great quality and great service, will be posting about it soon.

 

[esspressolungo]

Nice to hear from so many people about their opinions, thanks for joining in. Another question has come to my mind. Who would be able to install the RT gold valves here in Chiang Mai, I think it needs to be done by someone with profound knowledge, there's only a few shop in Chiang Mai that do shocks, but all they know is there standard program...I am still thinking of getting a kit for the 400.

By the way I still have the original XR400R springs, I would let them go for a cheap, if anyone is interested, I know they use those spring on many different models, great upgrade for the KDX and so forth

 

[crs]

Just a slight disagreement, general consensus is lighter oil is better, not heavier. Heavier oil you may get hydraulic lock or just slower damping action. There is a ton of research out, check it out for yourself!

Maybe you're right - but I can't find all this research... Would appreciate some links. I've found it difficult to get answers on the internet re. suspension setup (particularly oil weight) after changing springs - and the more I think about it, the more complicated it gets - lots of variables, different forks types (damping rod or cartridge) with different adjustability... Easy to understand why there are suspension specialists!

Some XR fork spring weights:

Xr600 93-00 : .41
Xr600 85-92 : .42
Xr650L 93-02: .44
Xr400 00-02 : .40
Xr400 96-99 : .38

The .38s (and .40s?) are often used in 95-06 KDX 200/220s as they match the diameter and suit the average rider weight better then the soft standards. (Bit longer then KDX standard so might want to change the spacer.)

EDIT: Rudi - google for 'XR400 shim stack mod', if you don't already know about that... (Done on later KDX cartridge forks too.)

 

[esspressolungo]

Thanks Chris, the shim stack mod I mentioned earlier in this thread, the best I could find is here:

Honda XR & XL Fork & Shock Spring Rate Per Rider's Weight on 4Strokes.com


Nice to seen it all in one place with different rider weight. I just found out that YSS is doing rear shocks for the 400 too, should be cheap enough to give it a try, I see them selling now in the U.K and New Zealand. I will call YSS and see if I can talk them into doing a custom shock for me with a heavier spring, I think 12.5 kg would be nice to start with.

I have the suspension almost perfectly dialled in, it is still soft in the rear, but the control of the front is great and even over rocky sections the bike behaves nice without tiring my arms, I think I will stick with this setup for now. But still want to talk to YSS and see if they can do something for me.

 

[esspressolungo]

Please forgive me if I bore you with more suspension craze here, but maybe some will find it helpful. I was still unsatisfied with the overall feel of my XR400, so I tried to find more spring rate calculators for my weight. I went to racetech and the calculation came up with 54kg for my weight, so one has to choose the nearest which is 47kg, but that's still far too soft for my kind of riding. On another website the calculator came up with 64 kg and 13.6kg on the rear, but neither Eibach or Racetech have those in stock and I didn't want odering another set of fork springs without being 100 % sure getting the right staff. After more searching I came across Home - Cannon Racecraft. I droped those guys an email and they got back to me in no time. I asked them a lot of questions and they all got replied very quickly and professional. Then I asked for the recommendation for my weight and they came up with 64kg front and 13.6 rear. so I went ahead and ordered those custom made springs. I installed them a couple of days ago and I am blown away by the quality and action of those springs, the first time I can dial in the suspension without compromising and it is spot on, the bike handle so much better now and the fatigue in the arms is almost gone and I can fly over most ruts and roots now, what a dream. So it really makes such a difference to have the right spring rates for your weight. Thank you Cannon Racecraft for your professional advise and the quick manufacturing and fast shipping, this was the best spent money on my bike so far, slowly I am getting what I want. Cheers