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Date: 09 Jun 2007 14:40:11
From: Bob Flumere
Subject: Fox Vanilla No Full Travel?
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Fox shock experts: I have a 2005 Fox Vanilla 130. When I disassemble this fork and remove the springs it will travel the full five inches. The bushings and tubes are not binding. After installing the springs, damper, spacers and oil (carefully by the "book") it only compresses about 4" when if I jump on it with my full weight (175 lbs.) The fork is all stock and has all the springs and the 30mm spacers in the correct places for 130mm travel and the correct oil levels both sides. Is this typical. Can the springs be coil binding at full compression, preventing the shock from traveling the last 2". If I remove both top caps (allowing the springs to extend freely), I can fully compress the fork. With correct spring for my weight from the Fox chart, I can only get about 3/4" of sag with the preload knob fully backed off. The ride is harsh and the fork "tops out" easily. A hard landing will only use about 3" of the travel. So, I have put the next lower rate spring (purple) into the left side to get anywhere near the proper sag (1") on my 2006 Heckler, but the total travel is still way short of the advertised 130mm. This spring is supposed to be for riders up to 155 lbs. and I am 175.. The Heckler is very smooth this way, but there is a lot more brake dive than with the higher rate spring. What is wrong with this picture, if anything ?? Is this the way Fox forks work normally?? How much of the advertised 130mm travel should you expect to see when pushing down on the bars with your full weight?? TIA Bob rflumere@comcast.net
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Date: 10 Jun 2007 16:19:53
From: Chris Nelson
Subject: Re: Fox Vanilla No Full Travel?
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On Jun 10, 4:52 pm, Bob Flumere <rflum...@comcast.net > wrote: > On Sun, 10 Jun 2007 12:35:34 -0700, SocSecTrainWr...@earthlink.net > wrote: > > > > > > > > >> Your welcome. To compensate for brake dive, shift your weight to the > >> back of the bike when braking. If you are still topping out, set your > >> rebound to be slower. > > >How would increasing rebound damping (making rebound slower) help with > >brake dive? It seems to me that it would not really have much effect > >on something that is essentially a compression problem. I think of > >rebound damping as slowing the fork extension motion when it is > >unloaded. If that's not correct, maybe I could learn something. > > >I checked out the Heckler on the Santa Cruz website. Since it's a FS, > >it seems like excessive sag on the rear could change the front angle > >in a way that would lighten the front and change the angle of force > >applied to the shock on landing in a way that would make it harder to > >compress. > > Very true... > > Actually the fact that it is a Vanilla "R" means that it does not have > an external adustment for Compression damping, (only Rebound), and > that was what the discussion was about, relating to "Brake Dive".. > > ie: More compression damping might (or might not <G>) reduce the > tendency toward "Brake Dive". > > Your point about the rear sag is also well taken, but the rear shock > is also pressurized (Fox Air shock) to sag the rear end of the bike > about 1" of the total 5.5" of travel, when I am in my normal riding > position.. > > Sooo.. when getting on the bike and assuming my normal riding posture, > this bike is "sagging" approximately equal amounts front and rear. > This is the way I have set up most of my other FS bikes.. > That is to say, nearly equal suspension sag both front and rear when > in the normal riding posture. > The one inch being 20% - 25% or so of the total travel. > > P.S. I took the bike (a Heckler) for a long ride today with the > softer rate spring in the the fork and it not only has made the front > end softer and much more forgiving on my arms and shoulders, but also > seems to make the bike much more supple in general and improves the > climbing ability because it is no longer "topping out" the fork when > climbing and doesn't require exagerated forward body position to keep > the front tire tracking well.. > > My loosely fitted tie wrap showed that I used only about 3 7/8" of the > "Advertised" 5" of travel, but I didn't do or land any hard drops > wrong today. I am going to guess that this is how this fork supposed > to work, and I won't ever see the full 5" of travel unless I land a > big one very badly.. <G> > > Hope I don't take a trip over the bars while getting accustomed to > this new feel. <BG> > > Thanks fer the comments all! > > Bob- Hide quoted text - > > - Show quoted text - Ah yes, that's how that fork is supposed to feel. You cannot beat the ride of that fork. Just make sure that the oil level is correct as that could limit travel. Chris
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Date: 10 Jun 2007 12:35:34
From:
Subject: Re: Fox Vanilla No Full Travel?
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On Jun 10, 7:21 am, Chris Nelson <smilin...@hotmail.com > wrote: > On Jun 10, 6:57 am, Bob Flumere <rflum...@comcast.net> wrote: > > > > > On Sat, 09 Jun 2007 18:13:29 -0700, Chris Nelson > > > <smilin...@hotmail.com> wrote: > > >On Jun 9, 9:02 pm, Chris Nelson <smilin...@hotmail.com> wrote: > > >> On Jun 9, 7:44 pm, Bob Flumere <rflum...@comcast.net> wrote: > > > >> > On Sat, 09 Jun 2007 16:28:10 -0700, Chris Nelson > > > >> > <smilin...@hotmail.com> wrote: > > > >> > >> How much of the advertised 130mm travel should you expect to see when > > >> > >> pushing down on the bars with your full weight?? > > > >> > >> TIA > > > >> > >> Bob > > > >> > >> rflum...@comcast.net > > > >> OK, but your math doesn't add up. You say it compresses 4" and it > > >> doesn't go the final 2", yet is is a 130mm which is 5". > > > >> 2 + 4 = 5 ??? > > > >> Your sag should be more like 1" or 1.25" so the spring you have in > > >> there is probably too stiff. I would swap it out with the next softer > > >> spring regardless of what the manual says for your weight. The key > > >> measurement is sag. > > > >> Chris > > > >> Chris- Hide quoted text - > > > >> - Show quoted text - > > > >If the fork is a Vanilla RLC, then you should be able to adust for > > >less brake dive, if its the Vanilla R then you can't. > > > >Does it bottom out(clunk) when you jump on it? If not I wouldn't worry > > >about that extra bit of travel you are missing. The best way you tell > > >how much travel you use is to put a twist tie on the stanchion that > > >will remember the max travel during your ride. You should never bottom > > >the fork out as that will cause damage. It you are traveling 4 to 4.5 > > >out of the 5 during a ride, then you are golden. > > > >Chris > > > Chris.. > > > Sorry about the math..<G> > > > The tie wrap on the leg method is how I have been measuring the > > travel, and with the softer spring, I see slightly less than 4" after > > a hard landing. So, I am really missing about 1" of the "Advertised" > > travel.. > > > It does not klunk or bottom out hard under any circumstance. > > > The only way I can get the 1" of sag (20-25% of "advertised" travel) > > is to use the softer spring. With this spring in, the sag is about 1" > > with the preload adjustment near the center of its travel.. the only > > thing that does not make sense is that this spring is for a rider > > weight of 30 lbs. less than I.. > > > The bike (SantaCruz Heckler) rides very nicely > > set up this way, but I hope I will not become a candidate for going > > over the bars more easily.<G> It is a Vanilla R, so there is no > > external compression damping adjustment. > > > Thanks for the comments... > > > Bob.- Hide quoted text - > > > - Show quoted text - > > Your welcome. To compensate for brake dive, shift your weight to the > back of the bike when braking. If you are still topping out, set your > rebound to be slower. How would increasing rebound damping (making rebound slower) help with brake dive? It seems to me that it would not really have much effect on something that is essentially a compression problem. I think of rebound damping as slowing the fork extension motion when it is unloaded. If that's not correct, maybe I could learn something. I checked out the Heckler on the Santa Cruz website. Since it's a FS, it seems like excessive sag on the rear could change the front angle in a way that would lighten the front and change the angle of force applied to the shock on landing in a way that would make it harder to compress.
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Date: 10 Jun 2007 16:52:25
From: Bob Flumere
Subject: Re: Fox Vanilla No Full Travel?
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On Sun, 10 Jun 2007 12:35:34 -0700, SocSecTrainWreck@earthlink.net wrote: >> >> Your welcome. To compensate for brake dive, shift your weight to the >> back of the bike when braking. If you are still topping out, set your >> rebound to be slower. > >How would increasing rebound damping (making rebound slower) help with >brake dive? It seems to me that it would not really have much effect >on something that is essentially a compression problem. I think of >rebound damping as slowing the fork extension motion when it is >unloaded. If that's not correct, maybe I could learn something. > >I checked out the Heckler on the Santa Cruz website. Since it's a FS, >it seems like excessive sag on the rear could change the front angle >in a way that would lighten the front and change the angle of force >applied to the shock on landing in a way that would make it harder to >compress. Very true... Actually the fact that it is a Vanilla "R" means that it does not have an external adustment for Compression damping, (only Rebound), and that was what the discussion was about, relating to "Brake Dive".. ie: More compression damping might (or might not <G >) reduce the tendency toward "Brake Dive". Your point about the rear sag is also well taken, but the rear shock is also pressurized (Fox Air shock) to sag the rear end of the bike about 1" of the total 5.5" of travel, when I am in my normal riding position.. Sooo.. when getting on the bike and assuming my normal riding posture, this bike is "sagging" approximately equal amounts front and rear. This is the way I have set up most of my other FS bikes.. That is to say, nearly equal suspension sag both front and rear when in the normal riding posture. The one inch being 20% - 25% or so of the total travel. P.S. I took the bike (a Heckler) for a long ride today with the softer rate spring in the the fork and it not only has made the front end softer and much more forgiving on my arms and shoulders, but also seems to make the bike much more supple in general and improves the climbing ability because it is no longer "topping out" the fork when climbing and doesn't require exagerated forward body position to keep the front tire tracking well.. My loosely fitted tie wrap showed that I used only about 3 7/8" of the "Advertised" 5" of travel, but I didn't do or land any hard drops wrong today. I am going to guess that this is how this fork supposed to work, and I won't ever see the full 5" of travel unless I land a big one very badly.. <G > Hope I don't take a trip over the bars while getting accustomed to this new feel. <BG > Thanks fer the comments all! Bob
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Date: 10 Jun 2007 04:21:47
From: Chris Nelson
Subject: Re: Fox Vanilla No Full Travel?
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On Jun 10, 6:57 am, Bob Flumere <rflum...@comcast.net > wrote: > On Sat, 09 Jun 2007 18:13:29 -0700, Chris Nelson > > > > > > <smilin...@hotmail.com> wrote: > >On Jun 9, 9:02 pm, Chris Nelson <smilin...@hotmail.com> wrote: > >> On Jun 9, 7:44 pm, Bob Flumere <rflum...@comcast.net> wrote: > > >> > On Sat, 09 Jun 2007 16:28:10 -0700, Chris Nelson > > >> > <smilin...@hotmail.com> wrote: > > >> > >> How much of the advertised 130mm travel should you expect to see when > >> > >> pushing down on the bars with your full weight?? > > >> > >> TIA > > >> > >> Bob > > >> > >> rflum...@comcast.net > > >> OK, but your math doesn't add up. You say it compresses 4" and it > >> doesn't go the final 2", yet is is a 130mm which is 5". > > >> 2 + 4 = 5 ??? > > >> Your sag should be more like 1" or 1.25" so the spring you have in > >> there is probably too stiff. I would swap it out with the next softer > >> spring regardless of what the manual says for your weight. The key > >> measurement is sag. > > >> Chris > > >> Chris- Hide quoted text - > > >> - Show quoted text - > > >If the fork is a Vanilla RLC, then you should be able to adust for > >less brake dive, if its the Vanilla R then you can't. > > >Does it bottom out(clunk) when you jump on it? If not I wouldn't worry > >about that extra bit of travel you are missing. The best way you tell > >how much travel you use is to put a twist tie on the stanchion that > >will remember the max travel during your ride. You should never bottom > >the fork out as that will cause damage. It you are traveling 4 to 4.5 > >out of the 5 during a ride, then you are golden. > > >Chris > > Chris.. > > Sorry about the math..<G> > > The tie wrap on the leg method is how I have been measuring the > travel, and with the softer spring, I see slightly less than 4" after > a hard landing. So, I am really missing about 1" of the "Advertised" > travel.. > > It does not klunk or bottom out hard under any circumstance. > > The only way I can get the 1" of sag (20-25% of "advertised" travel) > is to use the softer spring. With this spring in, the sag is about 1" > with the preload adjustment near the center of its travel.. the only > thing that does not make sense is that this spring is for a rider > weight of 30 lbs. less than I.. > > The bike (SantaCruz Heckler) rides very nicely > set up this way, but I hope I will not become a candidate for going > over the bars more easily.<G> It is a Vanilla R, so there is no > external compression damping adjustment. > > Thanks for the comments... > > Bob.- Hide quoted text - > > - Show quoted text - Your welcome. To compensate for brake dive, shift your weight to the back of the bike when braking. If you are still topping out, set your rebound to be slower. Don't worry about using the spring that the book says, the book is wrong alot. The sag will set you free. If the spring was really too soft for you, then you would bottom out(clunk). Chris
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Date: 09 Jun 2007 18:13:29
From: Chris Nelson
Subject: Re: Fox Vanilla No Full Travel?
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On Jun 9, 9:02 pm, Chris Nelson <smilin...@hotmail.com > wrote: > On Jun 9, 7:44 pm, Bob Flumere <rflum...@comcast.net> wrote: > > > > > > > On Sat, 09 Jun 2007 16:28:10 -0700, Chris Nelson > > > <smilin...@hotmail.com> wrote: > > > >> How much of the advertised 130mm travel should you expect to see when > > >> pushing down on the bars with your full weight?? > > > >> TIA > > > >> Bob > > > >> rflum...@comcast.net > > > >That particular fork is internally convertable between 100mm and 130mm > > >of travel. It might be set up for 100mm. The way to tell is to measure > > >the Axel to Crown distance with the fork unweighted. If it measures > > >around 490mm then its set up for 100mm, 520 and its 130mm. > > > >Fox used to have the conversion procedure on their website. > > > >Chris > > > Chris.. > > > Yes, good point, and it does measure 520mm to the crown. But you > > raise the question that I have asked myself, and that is, are all of > > the travel spacers in the correct places..?? > > > The pictures in the diagrams relating to changing the travel from > > 100mm to 130mm are terrible, but it seems that everything is in the > > correct relationships to me. If you put the LH travel spacer below > > the rebound spring and leave the RH one out.. this would pull the > > total Axle to Crown distance down the 30mm to 490mm.. and thus reduce > > the advertised travel to 100mm. > > > In my case, the LH travel spacer is under the top cap, where it > > belongs according to the diagrams, and the RH spacer is also under the > > top cap (where it shows in the diags.. ) If you leave either one of > > these out, the springs do not even come close to either cap, and thus > > would be completely out of the picture until the fork was compressed > > the 30mm that these spacers take up. I think that I will measure the > > spring stack at the 100mm that the fork will (barely) travel and see > > if the springs are coil binding and preventing the fork from > > travelling the rest of the (advertised) travel. > > > Does anyone out there have one of these and be willing to stand (or > > sit) on the handle bars and tell me how much fork travel they are > > really seeing.??? > > > Please...?? > > > Bob > > > rflum...@comcast.net- Hide quoted text - > > > - Show quoted text - > > OK, but your math doesn't add up. You say it compresses 4" and it > doesn't go the final 2", yet is is a 130mm which is 5". > > 2 + 4 = 5 ??? > > Your sag should be more like 1" or 1.25" so the spring you have in > there is probably too stiff. I would swap it out with the next softer > spring regardless of what the manual says for your weight. The key > measurement is sag. > > Chris > > Chris- Hide quoted text - > > - Show quoted text - If the fork is a Vanilla RLC, then you should be able to adust for less brake dive, if its the Vanilla R then you can't. Does it bottom out(clunk) when you jump on it? If not I wouldn't worry about that extra bit of travel you are missing. The best way you tell how much travel you use is to put a twist tie on the stanchion that will remember the max travel during your ride. You should never bottom the fork out as that will cause damage. It you are traveling 4 to 4.5 out of the 5 during a ride, then you are golden. Chris
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Date: 10 Jun 2007 06:57:54
From: Bob Flumere
Subject: Re: Fox Vanilla No Full Travel?
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On Sat, 09 Jun 2007 18:13:29 -0700, Chris Nelson <smilin321@hotmail.com > wrote: >On Jun 9, 9:02 pm, Chris Nelson <smilin...@hotmail.com> wrote: >> On Jun 9, 7:44 pm, Bob Flumere <rflum...@comcast.net> wrote: >> >> >> >> >> >> > On Sat, 09 Jun 2007 16:28:10 -0700, Chris Nelson >> >> > <smilin...@hotmail.com> wrote: >> >> > >> How much of the advertised 130mm travel should you expect to see when >> > >> pushing down on the bars with your full weight?? >> >> > >> TIA >> >> > >> Bob >> >> > >> rflum...@comcast.net >> >> OK, but your math doesn't add up. You say it compresses 4" and it >> doesn't go the final 2", yet is is a 130mm which is 5". >> >> 2 + 4 = 5 ??? >> >> Your sag should be more like 1" or 1.25" so the spring you have in >> there is probably too stiff. I would swap it out with the next softer >> spring regardless of what the manual says for your weight. The key >> measurement is sag. >> >> Chris >> >> Chris- Hide quoted text - >> >> - Show quoted text - > >If the fork is a Vanilla RLC, then you should be able to adust for >less brake dive, if its the Vanilla R then you can't. > >Does it bottom out(clunk) when you jump on it? If not I wouldn't worry >about that extra bit of travel you are missing. The best way you tell >how much travel you use is to put a twist tie on the stanchion that >will remember the max travel during your ride. You should never bottom >the fork out as that will cause damage. It you are traveling 4 to 4.5 >out of the 5 during a ride, then you are golden. > >Chris Chris.. Sorry about the math..<G > The tie wrap on the leg method is how I have been measuring the travel, and with the softer spring, I see slightly less than 4" after a hard landing. So, I am really missing about 1" of the "Advertised" travel.. It does not klunk or bottom out hard under any circumstance. The only way I can get the 1" of sag (20-25% of "advertised" travel) is to use the softer spring. With this spring in, the sag is about 1" with the preload adjustment near the center of its travel.. the only thing that does not make sense is that this spring is for a rider weight of 30 lbs. less than I.. The bike (SantaCruz Heckler) rides very nicely set up this way, but I hope I will not become a candidate for going over the bars more easily.<G > It is a Vanilla R, so there is no external compression damping adjustment. Thanks for the comments... Bob.
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Date: 09 Jun 2007 18:02:11
From: Chris Nelson
Subject: Re: Fox Vanilla No Full Travel?
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On Jun 9, 7:44 pm, Bob Flumere <rflum...@comcast.net > wrote: > On Sat, 09 Jun 2007 16:28:10 -0700, Chris Nelson > > > > > > <smilin...@hotmail.com> wrote: > > >> How much of the advertised 130mm travel should you expect to see when > >> pushing down on the bars with your full weight?? > > >> TIA > > >> Bob > > >> rflum...@comcast.net > > >That particular fork is internally convertable between 100mm and 130mm > >of travel. It might be set up for 100mm. The way to tell is to measure > >the Axel to Crown distance with the fork unweighted. If it measures > >around 490mm then its set up for 100mm, 520 and its 130mm. > > >Fox used to have the conversion procedure on their website. > > >Chris > > Chris.. > > Yes, good point, and it does measure 520mm to the crown. But you > raise the question that I have asked myself, and that is, are all of > the travel spacers in the correct places..?? > > The pictures in the diagrams relating to changing the travel from > 100mm to 130mm are terrible, but it seems that everything is in the > correct relationships to me. If you put the LH travel spacer below > the rebound spring and leave the RH one out.. this would pull the > total Axle to Crown distance down the 30mm to 490mm.. and thus reduce > the advertised travel to 100mm. > > In my case, the LH travel spacer is under the top cap, where it > belongs according to the diagrams, and the RH spacer is also under the > top cap (where it shows in the diags.. ) If you leave either one of > these out, the springs do not even come close to either cap, and thus > would be completely out of the picture until the fork was compressed > the 30mm that these spacers take up. I think that I will measure the > spring stack at the 100mm that the fork will (barely) travel and see > if the springs are coil binding and preventing the fork from > travelling the rest of the (advertised) travel. > > Does anyone out there have one of these and be willing to stand (or > sit) on the handle bars and tell me how much fork travel they are > really seeing.??? > > Please...?? > > Bob > > rflum...@comcast.net- Hide quoted text - > > - Show quoted text - OK, but your math doesn't add up. You say it compresses 4" and it doesn't go the final 2", yet is is a 130mm which is 5". 2 + 4 = 5 ??? Your sag should be more like 1" or 1.25" so the spring you have in there is probably too stiff. I would swap it out with the next softer spring regardless of what the manual says for your weight. The key measurement is sag. Chris Chris
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Date: 09 Jun 2007 16:28:10
From: Chris Nelson
Subject: Re: Fox Vanilla No Full Travel?
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On Jun 9, 2:40 pm, Bob Flumere <rflum...@comcast.net > wrote: > Fox shock experts: > > I have a 2005 Fox Vanilla 130. > > When I disassemble this fork and remove the springs it will travel the > full five inches. The bushings and tubes are not binding. > > After installing the springs, damper, spacers and oil (carefully by > the "book") it only compresses about 4" when if I jump on it with my > full weight (175 lbs.) > > The fork is all stock and has all the springs and the 30mm spacers in > the correct places for 130mm travel and the correct oil levels both > sides. > > Is this typical. Can the springs be coil binding at full compression, > preventing the shock from traveling the last 2". > > If I remove both top caps (allowing the springs to extend freely), I > can fully compress the fork. > > With correct spring for my weight from the Fox chart, I can only get > about 3/4" of sag with the preload knob fully backed off. The ride is > harsh and the fork "tops out" easily. A hard landing will only use > about 3" of the travel. > > So, I have put the next lower rate spring (purple) into the left side > to get anywhere near the proper sag (1") on my 2006 Heckler, but > the total travel is still way short of the advertised 130mm. > This spring is supposed to be for riders up to 155 lbs. and I am 175.. > The Heckler is very smooth this way, but there is a lot more brake > dive than with the higher rate spring. > > What is wrong with this picture, if anything ?? > > Is this the way Fox forks work normally?? > > How much of the advertised 130mm travel should you expect to see when > pushing down on the bars with your full weight?? > > TIA > > Bob > > rflum...@comcast.net That particular fork is internally convertable between 100mm and 130mm of travel. It might be set up for 100mm. The way to tell is to measure the Axel to Crown distance with the fork unweighted. If it measures around 490mm then its set up for 100mm, 520 and its 130mm. Fox used to have the conversion procedure on their website. Chris
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Date: 09 Jun 2007 19:44:57
From: Bob Flumere
Subject: Re: Fox Vanilla No Full Travel?
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On Sat, 09 Jun 2007 16:28:10 -0700, Chris Nelson <smilin321@hotmail.com > wrote: > >> >> How much of the advertised 130mm travel should you expect to see when >> pushing down on the bars with your full weight?? >> >> TIA >> >> Bob >> >> rflum...@comcast.net > >That particular fork is internally convertable between 100mm and 130mm >of travel. It might be set up for 100mm. The way to tell is to measure >the Axel to Crown distance with the fork unweighted. If it measures >around 490mm then its set up for 100mm, 520 and its 130mm. > >Fox used to have the conversion procedure on their website. > >Chris Chris.. Yes, good point, and it does measure 520mm to the crown. But you raise the question that I have asked myself, and that is, are all of the travel spacers in the correct places..?? The pictures in the diagrams relating to changing the travel from 100mm to 130mm are terrible, but it seems that everything is in the correct relationships to me. If you put the LH travel spacer below the rebound spring and leave the RH one out.. this would pull the total Axle to Crown distance down the 30mm to 490mm.. and thus reduce the advertised travel to 100mm. In my case, the LH travel spacer is under the top cap, where it belongs according to the diagrams, and the RH spacer is also under the top cap (where it shows in the diags.. ) If you leave either one of these out, the springs do not even come close to either cap, and thus would be completely out of the picture until the fork was compressed the 30mm that these spacers take up. I think that I will measure the spring stack at the 100mm that the fork will (barely) travel and see if the springs are coil binding and preventing the fork from travelling the rest of the (advertised) travel. Does anyone out there have one of these and be willing to stand (or sit) on the handle bars and tell me how much fork travel they are really seeing.??? Please...?? Bob rflumere@comcast.net
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Date: 09 Jun 2007 15:53:46
From:
Subject: Re: Fox Vanilla No Full Travel?
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On Jun 9, 1:40 pm, Bob Flumere <rflum...@comcast.net > wrote: > Fox shock experts: > > I have a 2005 Fox Vanilla 130. > > When I disassemble this fork and remove the springs it will travel the > full five inches. The bushings and tubes are not binding. > > After installing the springs, damper, spacers and oil (carefully by > the "book") it only compresses about 4" when if I jump on it with my > full weight (175 lbs.) > > The fork is all stock and has all the springs and the 30mm spacers in > the correct places for 130mm travel and the correct oil levels both > sides. > > Is this typical. Can the springs be coil binding at full compression, > preventing the shock from traveling the last 2". > > If I remove both top caps (allowing the springs to extend freely), I > can fully compress the fork. > > With correct spring for my weight from the Fox chart, I can only get > about 3/4" of sag with the preload knob fully backed off. The ride is > harsh and the fork "tops out" easily. A hard landing will only use > about 3" of the travel. > > So, I have put the next lower rate spring (purple) into the left side > to get anywhere near the proper sag (1") on my 2006 Heckler, but > the total travel is still way short of the advertised 130mm. > This spring is supposed to be for riders up to 155 lbs. and I am 175.. > The Heckler is very smooth this way, but there is a lot more brake > dive than with the higher rate spring. > > What is wrong with this picture, if anything ?? > > Is this the way Fox forks work normally?? > > How much of the advertised 130mm travel should you expect to see when > pushing down on the bars with your full weight?? One other thing: 130mm is relatively long travel, so the bike geometry needs to be designed for it to take full advantage of the travel.
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Date: 09 Jun 2007 15:47:24
From:
Subject: Re: Fox Vanilla No Full Travel?
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On Jun 9, 1:40 pm, Bob Flumere <rflum...@comcast.net > wrote: > Fox shock experts: > > I have a 2005 Fox Vanilla 130. > > When I disassemble this fork and remove the springs it will travel the > full five inches. The bushings and tubes are not binding. > > After installing the springs, damper, spacers and oil (carefully by > the "book") it only compresses about 4" when if I jump on it with my > full weight (175 lbs.) > > The fork is all stock and has all the springs and the 30mm spacers in > the correct places for 130mm travel and the correct oil levels both > sides. > > Is this typical. Can the springs be coil binding at full compression, > preventing the shock from traveling the last 2". > > If I remove both top caps (allowing the springs to extend freely), I > can fully compress the fork. > > With correct spring for my weight from the Fox chart, I can only get > about 3/4" of sag with the preload knob fully backed off. The ride is > harsh and the fork "tops out" easily. A hard landing will only use > about 3" of the travel. > > So, I have put the next lower rate spring (purple) into the left side > to get anywhere near the proper sag (1") on my 2006 Heckler, but > the total travel is still way short of the advertised 130mm. > This spring is supposed to be for riders up to 155 lbs. and I am 175.. > The Heckler is very smooth this way, but there is a lot more brake > dive than with the higher rate spring. > > What is wrong with this picture, if anything ?? > > Is this the way Fox forks work normally?? > > How much of the advertised 130mm travel should you expect to see when > pushing down on the bars with your full weight?? I would expect that if you get the full travel without the top caps, you would get that minus the height of the internal part of the top cap with the top cap installed, and that travel would decrease further as you increase the preload. I am no expert on suspensions, so I could be completely wrong about this, but that is what I would expect. This assumes that the fork is in good shape and is not binding somehow. The fact that you don't get the proper sag for your weight with the recommended springs is interesting but not definitive in my mind, because it might be affected by your position on the bike and probably other factors. It sounds like you have it dialed in better with the single softer spring. It is natural to have more brake dive and I don't think there is an easy way to cure that short of an active suspension. I remember that motorcycles with variable valving to reduce brake dive were criticized as having a cure worse than the disease. If your fork has oil, which it sounds like it would, you might try going to a slightly heavier weight to slow the fork motion down some and see if you like that better, or increase compression damping if that is adjustable, but I think that if the fork feels good over sharp bumps I would not worry about brake dive.. If all this fails you might try to find someone who actually knows what they are talking about and ask them for advice.
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