Questions for Terry Hay on your top out spring.

MoG
We aren't meant to discuss products in this forum. The reactive springs are not for sale as seperate items as they are combined with other modifications which are performed by trained personnel. To simply purchase and install the springs by themselves would leave you well short of the full benefit.
Sorry
Terry Hay

MoG
The reason for the price was quite simply that a value needed to be placed on the mod for the sake of the readers. We have also had the mod reviewed by Dirt Rider magazine in the US. This will be printed in the February issue. To say it went well would be an understatement. We do not have an installer in Singapore at this stage. Due to the varying complexity of the installation requirements of Reactive suspension we insist on having trained personnel perform the work. This would ensure that everyone enjoys the full benefit without any drawbacks.
Regards
Terry Hay

Mogwai.
I agree with Terry 110% on this, I have seen many forks damaged beyond repair by so called great mechanics, it seems to be the better they are alleged to be the worse their mistakes are.
Race Tech have shot themselves in the foot big time with this, for example they send out a video for installing gold valves on motocross forks with all street bike kits, this video is no use at all the forks are barely even similar.
I have seen many many gold valve kits installed wrongly.
Rider says this Race Tech stuff is a piece of **** it doesn't work, tells all his friends, posts it on forums, lets the world know, Race Tech soon develops horrendous reputation. When you strip the forks it's not the product thats at fault it's the fact it's been installed wrongly.
Does the rider then go and tell all his friends, post messages on forums saying he was a complete dork and installed his kit wrong?

MoGwai
I have been approached by a couple if people to conduct a training seminar in both Malaysia and Singapore. Both times I have voiced my willingness to participate and have not heard anything further. It's a shame because I know there are people like yourself who are keen to upgrade their suspension or simply their knowledge on the subject. We have several workshops in Australia who have aligned themselves with our company. This has allowed both customers and agents to benefit from an expanded technical base and support network. I see no reason why there couldn't be an agent in Singapore if they met the requirements.
Regards
Terry Hay

I'm curious as to how that reactive spring works. Where can I find more info on the subject? Does it work on the same principle as the top-out spring in recent Showa shocks (Honda cr250 and crf). I guess it would basically act as a progressive spring only early in the travel where the other spring comes in to play, right? Would this setup work on forks equiped with air tanks?

Hey Terry and Mog,

ya have forgotten about me! I was once RaceTech appointed dealer and tuner in singapore.

RaceTech ex-manager Mr Callen have invite me to his office for a chat with me on the last day of course when i was leaving.

I got the dealership and have started a small little business here, but have no choice but to close due to financial problem. there are not many dirt rider in singapore who are really interested in setting up proper suspension but would rather throw $$ into making the bike more horsepower. however, i do know some hardcore dirt biker know the importance of well suspended machine.

Sorry Mog, I'm unable to help ya with this but would be able to advise ya on how to install the Reactive spring if ya got them. i'm only doing some revalving work on my personal bike for now. no time for ya guys.

Originally posted by terry hay
MoGwai
I have been approached by a couple if people to conduct a training seminar in both Malaysia and Singapore. Both times I have voiced my willingness to participate and have not heard anything further. It's a shame because I know there are people like yourself who are keen to upgrade their suspension or simply their knowledge on the subject. We have several workshops in Australia who have aligned themselves with our company. This has allowed both customers and agents to benefit from an expanded technical base and support network. I see no reason why there couldn't be an agent in Singapore if they met the requirements.
Regards
Terry Hay

Click to expand...

yupper, do I happen to know ya?

i have read about the Reactive stuff in a magazine, can't really remembered which one.

Terry, ya were mentioning about coming over to singapore to give a talk or some clinic about suspension, what's the outcome, no news from Andrew?
Do ya still in contact with Kaipo? I believe he is the mechanic for Grant Langston and he should be able hook up ya Reactive spring and let the pro have a go at it and listen to the comment?

see ya

Terry,
Is it possible to explain the theory behind the top out spring modification without going in to specifics of how it's achieved.
Why you felt the need for it and the benefits of such a system etc?
I've done a lot of work with top out springs for road race use in forks and shocks to help with various geometry and grip issues so I'm interested in their uses on dirt bikes.

svi - Sorry to be off topic here but are you living in Northern or Southern Ireland? Send me an email sometime will you, curious if I've met you before! harrispj@tcd.ie

Thanks

SVI
Like yourself I have been very involved in roadracing for the past few years. We have worked with many Australian champions and factory teams. In 2002 I ran the team for Kawasaki Australia under a caretaker role and this year we directed our efforts towards the 600 Supersport category. After working with R1s, GSXR1000s and ZX6rrs it became apparent there were problems with maximising the power output of these machines. The GSXR because it's COG was too high and it's wheel base too short for it's powerplant. The R1 and ZX6 because of the excessive fork extention. The concept behind our topout spring idea was in contrast to popular thinking. There has been a lot of theory behind the use of varying top out springs in the past. The most popular would seem to be to allow the fork to extend under acceleration. As you would no doubt be aware, as the throttle is applied a chain pull moment occurs and the body of the motorcycle is inclined to rotate around the rear axle. This obviously makes the rear of the motorcycle squat and tends to elevate the front. Many manufacturers of both production and after market forks have been extending the travel of their forks and using relatively soft top out springs. This allows to front of the bike to rise, leaving the wheel in contact with the ground for an extended period increasing the period prior to the release of traction. Good in theory. But what if the opposite were true? We made significant gains in traction, steering input and change of direction by holding the front of the motorcycle down. As a bonus the higher powered machines were able to be accelerated earlier and harder due to the fact that the wheel maintained a higher proportion of weight improving the co-effeicient of friction. Naturally with more traction and trust in the front end riders were encouraged to ride even harder. Lap times fell and confidence grew. Due to the fact that 60% of our business is with dirt bikes, naturally the question was asked. After considerable testing and development me arrived at a combination involving spring length, rate and damping modifications matched to the requirements of the riders. As you can appreciate, the spring is housed in the very heart of the fork requiring specialised tools and methods in some instances for disassembly and reassembly. Hence the reason we have to be selective about installers. So far the results have been spectacular. ADB magazine have dubbed this the greatest suspension mod in the past ten years. It seems quite simple and yet works so well.
Regards
Terry

Terry

I would like to know if your "reative suspension" has been tested in a woods application (GNCC ECT) and very interested to find out the results. Unfortunatley I have not seen the ADB here in the USA to read up on this issue.

Thanks
Russ

Russ
Karel Kramer from Dirt Rider magazine currently has them installed in his 300EXC KTM. He seems to be very happy with the results so far under enduro conditions. There will be a full report in their magazine in February.
Regards
Terry

Terry,
I'd been experimenting with the same thing so that riders could get hard on the gas exiting turns without running wide. Many tuners swear that you need the forks to extend to increase the degree of anti squat in the swing arm which allows you to drive harder, this would work fine but like you say the rate of weight transfer compressing the spring overcomes or cancels out the rate of extension caused by the anti squat. Some examples of shorter top out springs just seem to be looking at the point of initial action rather than the combined point of action, spring rate effects and coil bound length.

SVI
I would be happy to discuss my findings with you if you are interested. I left an e-mail address for you on the roadrace thread.
Regards
Terry