Re-Springing the Bike
Senior Member
Joined: Aug 2005
Posts: 5,917
Likes: 1
RE: Re-Springing the Bike
the big deal is how it holds up overtime. springs made initially for one spring rate, then rewounded for another spring rate? just doesn't sound right to me. sort of like bending a piece of metal once and then again..it loses integrity.
Senior Member
Joined: Aug 2006
Posts: 1,668
Likes: 0
From: Nebraska
RE: Re-Springing the Bike
sounds like they are trying to take the hard way out and save you alittle money. If you drilling and rewinding old parts, whats the point, they have mileage and abuse on them. I'd shell out a few extra bucks and send your forks out to a shop that specializes in suspension like jaybird said.
Senior Member
Joined: Oct 2006
Posts: 462
Likes: 0
RE: Re-Springing the Bike
Jaybird,
The more your talking about this place the more scared I'm getting for you...
To expand on what Tahoe wrote:
When a spring is cut or bent (not compressed, but actually bent) it actually changes the base material at a molecular level, making it harder and more brittle in that and the surrounding area. This in turn changes the rate of the spring in the area that is was cut and rebent, so now the spring has multiple rates(but not progressive) and is much more likely to break and a unaltered spring. If they don't have the CNC bending equipment, annealing furnace, shock/spring dyno (notjust pressuretester an actual shock/spring dyno). They don't have the correct equipment to modify springs.
For an engineer’s point of view, the ONLY pro of "modifying"a stock spring is the cost, but to me the cost difference is NOT worth the danger and risk. If you think about like this; say a year and a half from now, your going into a fast long corner (like the carousel at Road America), all of a sudden one of your spring brakes....your now skidding towards the hay bails and wall at over 80 mph, with your bike sliding right next you.... all of a sudden that $50 you saved, turned into $500 or morecrash damage to your bike, gear and yourself.
And there's a reason I didn't list Max, or Traxxion, but that's another story... Every one of the guys I listed is either a current or formerAMA suspension tech, or factory suspension engineer. They been doing this for years and years and they are the BEST at what they do (and yes GP suspensions is a great place as well). They have the tools,equipmentand the knowledge and experience to use them correctly (not just the "ideas"). I'm not saying get your stuff done by these guys, but when they give you advise I would listen to it very closely(like Dan @ Kyle racingloves to talk).
The more your talking about this place the more scared I'm getting for you...
To expand on what Tahoe wrote:
When a spring is cut or bent (not compressed, but actually bent) it actually changes the base material at a molecular level, making it harder and more brittle in that and the surrounding area. This in turn changes the rate of the spring in the area that is was cut and rebent, so now the spring has multiple rates(but not progressive) and is much more likely to break and a unaltered spring. If they don't have the CNC bending equipment, annealing furnace, shock/spring dyno (notjust pressuretester an actual shock/spring dyno). They don't have the correct equipment to modify springs.
For an engineer’s point of view, the ONLY pro of "modifying"a stock spring is the cost, but to me the cost difference is NOT worth the danger and risk. If you think about like this; say a year and a half from now, your going into a fast long corner (like the carousel at Road America), all of a sudden one of your spring brakes....your now skidding towards the hay bails and wall at over 80 mph, with your bike sliding right next you.... all of a sudden that $50 you saved, turned into $500 or morecrash damage to your bike, gear and yourself.
And there's a reason I didn't list Max, or Traxxion, but that's another story... Every one of the guys I listed is either a current or formerAMA suspension tech, or factory suspension engineer. They been doing this for years and years and they are the BEST at what they do (and yes GP suspensions is a great place as well). They have the tools,equipmentand the knowledge and experience to use them correctly (not just the "ideas"). I'm not saying get your stuff done by these guys, but when they give you advise I would listen to it very closely(like Dan @ Kyle racingloves to talk).
Thread Starter
|
Senior Member
Joined: May 2006
Posts: 3,477
Likes: 3
From: Prince George's County, MD
RE: Re-Springing the Bike
I agree with you on changing the spring at a molecular level. I inquired about that when they proposed the idea. They say that they have a lot of success with this method and they do have the equipment to do so. The say that the stock spring is plenty long and actually high quality, as well as the valves. Only problem is that the valves don't flow well, which is why they modify the stock componenets. According to the lady I spoke with, the only advantage I'd get with say...Traxxion's AK-20 kit is the manufacturing tolerances are tighter. However, there's no substitute for confidence in the equipment you're on, and I'm not hard up over $50 bucks.
They are a suspension shop, and it appears that it's the only thing they do.
They are a suspension shop, and it appears that it's the only thing they do.
Senior Member
Joined: Oct 2006
Posts: 462
Likes: 0
RE: Re-Springing the Bike
Don't get me wrong, I have zero problem with re-working the stock valves and changing the shim stack, hell thats what I'm racing on this year (but the stock valves in a F4i vs the 05/06 RR are a world of difference apart).
It's just that why anyone would be even try and re-work the stock springs are beyond me. They are correct that the stock springs are good quality to start with but they could easily be made into junk. Also I serousiouly doubt they thave the "correct" equipment to modify them, they may have some equipment that allows them to do it, but just not correctly. I say this becuase a CNC Spring bender, annealing furance and shock/spring dyno would run at or around a 1/2 million dollars together, used... To afford equipment like that they would have to be pushing a minium of $5 mil plus out the door every year.
It's just that why anyone would be even try and re-work the stock springs are beyond me. They are correct that the stock springs are good quality to start with but they could easily be made into junk. Also I serousiouly doubt they thave the "correct" equipment to modify them, they may have some equipment that allows them to do it, but just not correctly. I say this becuase a CNC Spring bender, annealing furance and shock/spring dyno would run at or around a 1/2 million dollars together, used... To afford equipment like that they would have to be pushing a minium of $5 mil plus out the door every year.
Thread Starter
|
Senior Member
Joined: May 2006
Posts: 3,477
Likes: 3
From: Prince George's County, MD
RE: Re-Springing the Bike
I just spoke with Dave @ GPSuspsensions and he's basically saying that he can do the front for $530 using the components they sell (including new springs). He says his stuff is better than Traxxion (of course he says that) and provided some reasons why. From our conversation, he suggests that my forks may have had some previous work done, but of course won't know until or unless he dissasembles them.
Here's the thing guys, I just don't experince the wallowing and sagging feeling that I should from the bike. Perhaps the front is good or perhaps I'm just that bad, I don't know the difference. I haven't had anyone with specific knowledge to ride the bike (would have been a good idea). I do however have that scary feelings sometimes riding really rough roads. Feels like the bike spends too much time hovering above the ground.
Under hard braking, is the front bottoming? Don't know. How would I find out?
The rear, yeah on stock setting (3) she squats under hard acceleration coming out of the turn. After the trackday I bumped her to 7. Couldn't evaluate on the street. Nevertheless, that bike will not be ridden again with a stock rear, since I've got the Ohlins sitting inthe box.
GP suspensions says that they Ohlins guy didn't provide all of the information I needed (I knew something was up with him) and that it's not as simple as saying the stock spring is too low (155-175lb). Dave says the rate is more important. He says that thespring I have may be marginally adequate and it's the minimum # on it that he'd want to see, but he'd have to have some sag #'s to know for sure.
He sounds very professional and sounds like he takes a scientific approach.
I want to have my forks to someone by middle next week. I can't wait too much longer otherwise I will not be able to take my class in March.
Here's the thing guys, I just don't experince the wallowing and sagging feeling that I should from the bike. Perhaps the front is good or perhaps I'm just that bad, I don't know the difference. I haven't had anyone with specific knowledge to ride the bike (would have been a good idea). I do however have that scary feelings sometimes riding really rough roads. Feels like the bike spends too much time hovering above the ground.
Under hard braking, is the front bottoming? Don't know. How would I find out?
The rear, yeah on stock setting (3) she squats under hard acceleration coming out of the turn. After the trackday I bumped her to 7. Couldn't evaluate on the street. Nevertheless, that bike will not be ridden again with a stock rear, since I've got the Ohlins sitting inthe box.
GP suspensions says that they Ohlins guy didn't provide all of the information I needed (I knew something was up with him) and that it's not as simple as saying the stock spring is too low (155-175lb). Dave says the rate is more important. He says that thespring I have may be marginally adequate and it's the minimum # on it that he'd want to see, but he'd have to have some sag #'s to know for sure.
He sounds very professional and sounds like he takes a scientific approach.
I want to have my forks to someone by middle next week. I can't wait too much longer otherwise I will not be able to take my class in March.
Senior Member
Joined: Aug 2005
Posts: 5,917
Likes: 1
RE: Re-Springing the Bike
jaybird...like i said before...the stock valves can be modified to make it work with your weight and very spirited riding you would be doing. go with that...with aftermarket springs with the right rate.
how much are they charging you for this work? i know they are local and all but it's possible to get a good deal with new parts...and be paying equal to or less than what that shop offers.
t
how much are they charging you for this work? i know they are local and all but it's possible to get a good deal with new parts...and be paying equal to or less than what that shop offers.
t
Thread Starter
|
Senior Member
Joined: May 2006
Posts: 3,477
Likes: 3
From: Prince George's County, MD
RE: Re-Springing the Bike
NO, not local. I'd have to ship out. I decided not to go with the local race shop. I can't reach anyone there most of the time. It's become a trust issue. I'd rather do business locally, but just can't. I may end up starting at the dealership to see what they can do for me. At least I've got a relationship with the guys in service.
Thread Starter
|
Senior Member
Joined: May 2006
Posts: 3,477
Likes: 3
From: Prince George's County, MD
RE: Re-Springing the Bike
So it sounds like you guys are saying that I should go with the modified valve option to save $200 bucks but spring for the new springs. (like that pun huh?)
Dave says that simply porting the stock valves and shimming the stack is still going to allow the suspension to bottom on hard braking. Sounds like you guys disagree.
Dave says that simply porting the stock valves and shimming the stack is still going to allow the suspension to bottom on hard braking. Sounds like you guys disagree.
Joined: Jun 2005
Posts: 771
Likes: 0
From:
RE: Re-Springing the Bike
ORIGINAL: Jaybird180
I just spoke with Dave @ GPSuspsensions and he's basically saying that he can do the front for $530 using the components they sell (including new springs). He says his stuff is better than Traxxion (of course he says that) and provided some reasons why. From our conversation, he suggests that my forks may have had some previous work done, but of course won't know until or unless he dissasembles them.
Here's the thing guys, I just don't experince the wallowing and sagging feeling that I should from the bike. Perhaps the front is good or perhaps I'm just that bad, I don't know the difference. I haven't had anyone with specific knowledge to ride the bike (would have been a good idea). I do however have that scary feelings sometimes riding really rough roads. Feels like the bike spends too much time hovering above the ground.
Under hard braking, is the front bottoming? Don't know. How would I find out?
The rear, yeah on stock setting (3) she squats under hard acceleration coming out of the turn. After the trackday I bumped her to 7. Couldn't evaluate on the street. Nevertheless, that bike will not be ridden again with a stock rear, since I've got the Ohlins sitting inthe box.
GP suspensions says that they Ohlins guy didn't provide all of the information I needed (I knew something was up with him) and that it's not as simple as saying the stock spring is too low (155-175lb). Dave says the rate is more important. He says that thespring I have may be marginally adequate and it's the minimum # on it that he'd want to see, but he'd have to have some sag #'s to know for sure.
He sounds very professional and sounds like he takes a scientific approach.
Please help me emotionally part with my dough. I want to have my forks to someone by middle next week. I can't wait too much longer otherwise I will not be able to take my class in March. I would also appreciate talking to one of you guys on the phone. Cell 240-391-4319 or PM me your # (even better if you have T-Mobile...free call!!!). 1,000,001 thanks.
I just spoke with Dave @ GPSuspsensions and he's basically saying that he can do the front for $530 using the components they sell (including new springs). He says his stuff is better than Traxxion (of course he says that) and provided some reasons why. From our conversation, he suggests that my forks may have had some previous work done, but of course won't know until or unless he dissasembles them.
Here's the thing guys, I just don't experince the wallowing and sagging feeling that I should from the bike. Perhaps the front is good or perhaps I'm just that bad, I don't know the difference. I haven't had anyone with specific knowledge to ride the bike (would have been a good idea). I do however have that scary feelings sometimes riding really rough roads. Feels like the bike spends too much time hovering above the ground.
Under hard braking, is the front bottoming? Don't know. How would I find out?
The rear, yeah on stock setting (3) she squats under hard acceleration coming out of the turn. After the trackday I bumped her to 7. Couldn't evaluate on the street. Nevertheless, that bike will not be ridden again with a stock rear, since I've got the Ohlins sitting inthe box.
GP suspensions says that they Ohlins guy didn't provide all of the information I needed (I knew something was up with him) and that it's not as simple as saying the stock spring is too low (155-175lb). Dave says the rate is more important. He says that thespring I have may be marginally adequate and it's the minimum # on it that he'd want to see, but he'd have to have some sag #'s to know for sure.
He sounds very professional and sounds like he takes a scientific approach.
Please help me emotionally part with my dough. I want to have my forks to someone by middle next week. I can't wait too much longer otherwise I will not be able to take my class in March. I would also appreciate talking to one of you guys on the phone. Cell 240-391-4319 or PM me your # (even better if you have T-Mobile...free call!!!). 1,000,001 thanks.
).I have Dave's stuff and I think it rocks. my buddy got his gixxer done up with Traxxion and he complains every now and then. I don't think you'd be disappointed with GP Suspension. Dave works with AMA teams and will always support his stuff.