racetech fork mod
- Thread starter stuna
- Start date
FEGV S4101 rt part no . use hyperpro springs as they are progressive rate but you have to call them
got mine here High performance motorcycle suspension sales and service from EPM Performance Imports
got mine here High performance motorcycle suspension sales and service from EPM Performance Imports
arkkornkid
New Member
From what I read on the first page, just making sure I got it right: you're using both the hyperpro springs with the racetech emulator?
it's crazy, I went from a bike with fully adjustable front/rear suspension (which I never did get perfect) to one with an easier set-up.... but the front forks have entirely too much dive to them.
At least it seems like the springs are simple to swap out. <--- put as many S's in there as I could.
it's crazy, I went from a bike with fully adjustable front/rear suspension (which I never did get perfect) to one with an easier set-up.... but the front forks have entirely too much dive to them.
At least it seems like the springs are simple to swap out. <--- put as many S's in there as I could.
Copy of the email I received today from Jamie at Daugherty motor sports.
Seems to me that this is probably the best way to enhance the handling of our bikes. Of course a quality shock for the rear should be in the works as well. I'm planning on waiting for that till the stock shock starts to get soft. $290 seems reasonable for a quality suspension. I paid more then double that for the single front shock on my other bike. The pair of shocks on that bike set me back over $1300. Worth every penny. I have embarrassed many sport bikes with it.
Don.
Thanks for the kind words! Something to keep in mind about your bike is that it has damping rod style forks. Because of that you would need Gold Valve Emulators. Those make an improvement but it will not be as good as a cartridge fork. Getting your forks setup with GVE's and the correct rate springs and fluid weight would provide the best results. The cost for this service would be $290. Let me know if you need anything else!
Jamie Daugherty
(260)710-4049
[email protected]
Daugherty Motorsports - Motorcycle Suspension Performance and Modification
Seems to me that this is probably the best way to enhance the handling of our bikes. Of course a quality shock for the rear should be in the works as well. I'm planning on waiting for that till the stock shock starts to get soft. $290 seems reasonable for a quality suspension. I paid more then double that for the single front shock on my other bike. The pair of shocks on that bike set me back over $1300. Worth every penny. I have embarrassed many sport bikes with it.
Don.
Thanks for the kind words! Something to keep in mind about your bike is that it has damping rod style forks. Because of that you would need Gold Valve Emulators. Those make an improvement but it will not be as good as a cartridge fork. Getting your forks setup with GVE's and the correct rate springs and fluid weight would provide the best results. The cost for this service would be $290. Let me know if you need anything else!
Jamie Daugherty
(260)710-4049
[email protected]
Daugherty Motorsports - Motorcycle Suspension Performance and Modification
Well I spent the last couple days talking to experts in suspensions. Jamie actually sells a service, where he sets up a fork or shock for the environment you ride in. He doesn't use progressive springs, and won't. He buys his springs from Sonic. Send him your forks and tell him where and how you ride, he will set you up. So then I contacted Sonic requesting information about the springs they would recommend. I have included their reply below.
Don,
We do have springs in the correct size, they're the same ones most bikes
with 41mm conventional forks use. SV650, Nina 650, Super Hawk, etc.
I would recommend 0.95s. The only issue is that the stock springs are
pretty close to that rate, so I'm not sure you'd really see much of an
improvement. It might make more sense for you to just do the emulators and
fork oil first and see how that is, you can always drop in a set springs
afterward if you still have issues with bottoming under hard braking.
Thanks,
Rich
So, I think that is where I will start. I commend Rich and Sonic for their honesty. They had a sale, and could have taken my bucks. For those of us who weight less then 220# suited up, this might be the best way to get the forks under better control.
For more information on progressive vs single rate springs you will find this on their web site.
Straight-Rate Springs vs. Progressive Rate Springs
Over the last 20 years, one of the biggest changes in the aftermarket motorcycle suspension world has been the virtually complete switch from progressive rate springs to straight rate ones. I think it’s safe to say that there’s not a single reputable suspension tuner who advocates progressive springs. The question is why? What’s the problem with a progressive rate? Why are straight rate springs better?
One of the problems is that bikes, street bikes anyway, just don’t have enough travel to take advantage of progressive rates. The soft initial portion gets blown right through, leaving a limited amount of travel for the stiffer portion to deal with. This results in less compliance, less traction and a harsher ride. Another issue is damping; Damping rates, particularly rebound damping, need to be matched to the spring rate. With a progressive (i.e. variable) rate, that’s impossible. Damping is always a compromise and a progressive rate just makes the balancing act that much more difficult. Adding to the problem is that modern forks actually have 2 spring mediums, the steel coil and the air trapped inside. The air is intrinsically a highly progressive spring. Adding a progressively wound steel spring to the mix is just making a bad situation worse.
They have more info at their web site, check it out.
Don,
We do have springs in the correct size, they're the same ones most bikes
with 41mm conventional forks use. SV650, Nina 650, Super Hawk, etc.
I would recommend 0.95s. The only issue is that the stock springs are
pretty close to that rate, so I'm not sure you'd really see much of an
improvement. It might make more sense for you to just do the emulators and
fork oil first and see how that is, you can always drop in a set springs
afterward if you still have issues with bottoming under hard braking.
Thanks,
Rich
So, I think that is where I will start. I commend Rich and Sonic for their honesty. They had a sale, and could have taken my bucks. For those of us who weight less then 220# suited up, this might be the best way to get the forks under better control.
For more information on progressive vs single rate springs you will find this on their web site.
Straight-Rate Springs vs. Progressive Rate Springs
Over the last 20 years, one of the biggest changes in the aftermarket motorcycle suspension world has been the virtually complete switch from progressive rate springs to straight rate ones. I think it’s safe to say that there’s not a single reputable suspension tuner who advocates progressive springs. The question is why? What’s the problem with a progressive rate? Why are straight rate springs better?
One of the problems is that bikes, street bikes anyway, just don’t have enough travel to take advantage of progressive rates. The soft initial portion gets blown right through, leaving a limited amount of travel for the stiffer portion to deal with. This results in less compliance, less traction and a harsher ride. Another issue is damping; Damping rates, particularly rebound damping, need to be matched to the spring rate. With a progressive (i.e. variable) rate, that’s impossible. Damping is always a compromise and a progressive rate just makes the balancing act that much more difficult. Adding to the problem is that modern forks actually have 2 spring mediums, the steel coil and the air trapped inside. The air is intrinsically a highly progressive spring. Adding a progressively wound steel spring to the mix is just making a bad situation worse.
They have more info at their web site, check it out.
Setting up springs for race conditions is different than for street use, and 5.1 inches of travel is all you get with any spring. Hyperpro is a good enough company to design the softest part of the spring for its intended application. Our forks have no damping adjustment anyway, that's why I went with a progressive spring. Much better performance and not harsh in any street condition I've encountered to date, in comparison to the stockers. The racetech folks have single rate springs which they match up to the rider and level of ability, (yes they offer different spring rates). You'll find differing opinions on how to set up the bike, even if you're firmly entrenched in the linear camp of thought. IMO
I'll let you progressive spring guys know how it works out, as Rich says, I can always add springs later. I'm sure your bikes are working much better then stock by using the progressive springs, and with the gold valve, I'm sure mine will work better then stock as well. A few days ago while I was reading the link stuna provided about how the gold valves worked, I was thinking along the same lines as Rich, they stated in that link that in their opinion progressive springs were working opposite of what the gold valves try to achieve. I have no doubt that either way we go will be an improvement over stock. As joloy133 stated, we have no damping adjustments without the gold valves. He still doesn't have any adjustments of the damping, other then by using the right oil. stuna covered his bases by using both. I'm going out on a limb here, but unless we all get together and swap out bikes, and ride them through some mountain roads, back to back, we won't know for sure which works best. This could turn into a thread without end , much like who makes the best fuel, or oil.
There's a shop in town here who specialize in sport bike suspension setup. I've sent them an Email to see what it would cost to have them do a suspension setup for me on a non adjustable fork. Normally it's not that expensive since it's usually just a matter of turning a few screws just the right amount. But having to take the suspension apart and the cost of parts I'm sure will add quite a bit of cost. But then I won't be dealing with a trial and error situation nor will I have to do the work myself. I'll have proven professionals who've setup suspension for professional racers doing it so I'll know it's right. I just hope I can afford it.
Jon, keep us informed as to what they have to say, and if you can get any details out of them, please pass those nuggets of wisdom along as well. Stuff like what oil they prefer (I already bought Silkolene, but others may want to know), what weight of oil, and what they actually do as part of their service. One of the reasons I passed on the progressive springs (for now anyway) is because I made air adjustable forks for my 78 GS 750. They did help prevent bottoming of the forks, but damping suffered (I probably didn't have the right weight oil in them), and they could be harsh sometimes. The air forks worked as progressive springs would, but with some control over the spring rate, as all you had to do was change the air pressure. Did they improve my ride, nope, but they did prevent bottoming when set up with the right pressure. I really needed to do a lot more experimenting with that set up. I have a lot more time on my hands these days, maybe I should try the air fork concept again and play with it till I get it right.
Ok, I got the Gold Valves installed. I am very happy with the control the forks have now. At first I set them up for "race" with 4 turns in. After riding it that way for a few hours I went back and turned them down to 2 1/2 turns. I'm keeping the 2 1/2 turn adjustment. The forks are much better controlled. They keep the tire in contact with the asphalt, going over small irregularities better then stock, and the dampening is working as advertised. No wallowing, and a smoother ride. Do the forks bottom? I don't think so, if they are, they are hitting bottom gently. They do react to bumps in a corner much better then stock, following the road surface and keeping traction on the front end much better. As stuna commented earlier, the faults in the rear shock are more apparent now. I am beginning to feel more comfortable with the bike leaned over. I think my chicken strips are doomed.
what springs on the valve light / blue - or the heavy yellow ?
I went with the blue springs, after riding with them set at 4 turns, I can't imagine using the yellow springs. I used 10wt Slikolene fork oil, that is why the extra half turn on the valves. I was looking for a quick return on the rebound damping. The lighter the oil, the faster the rebound is, allowing the wheel to follow the road easier. The only drawback I can see with the emulators is, now I feel the need to spend a lot more money on the rear shock. The cost worked out to about $180 for the valves, oil and shipping. Since the fork was the weakest link on this bike, I feel that it was money well spent. I have Wilbers on my BMW, I love them. I'm hoping they come out with shocks for the 6R. The nice thing about the Wilbers is, they set them up custom for you according to weight, gear on the bike, if you ride 2 up, and riding style. In my case, the preset settings were perfect. At this point we don't have many options for a lot of parts. If Hyperpro is the only game in town, then they will get my money.
The cost worked out to about $180 for the valves, oil and shipping. Since the fork was the weakest link on this bike, I feel that it was money well spent. I have Wilbers on my BMW, I love them. I'm hoping they come out with shocks for the 6R. The nice thing about the Wilbers is, they set them up custom for you according to weight, gear on the bike, if you ride 2 up, and riding style. In my case, the preset settings were perfect. At this point we don't have many options for a lot of parts. If Hyperpro is the only game in town, then they will get my money.owldaddy, did you do this install yourself or have a shop do it? If you did it yourself how would you rate the skill level involved?
thanks!
kevin
I installed them myself. It wasn't to hard, just time consuming. I am a mechanic and do all my own work, I would say that most anyone who has a little mechanical ability should be able to do this job. If you look back in this thread, you will find a link that details the job on a cruiser. They even provide pictures, the same steps apply to the 6R. I think it was a link that stuna provided. The most difficult part was drilling the holes in the damper rod. If you have a drill and some basic hand tools you can do it. Having a air impact wrench makes getting the damper rod out easier. BTW I always place shims between the brake pads when taking the calipers off the forks, you don't want to squeeze the brake handle by accident and have the pads and pistons come out of the caliper bores. That can get messy, and would require a brake fluid flush as well.
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