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The maker will quote the amount the fork CAN travel - which doesn't necessarily mean you will get all the available travel. How stiff the spring is, the terrain you ride, your weight etc, all affect how much travel you can get out of the fork.

If you are curious, you can loosely fit a zip tie temporarily around one of the the uppers to see how much travel you are using on a ride.
 

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You can measure the distance from the wheel axle to the crown race(where the bottom of the head tube meets) and then subtract a certain distance(I forgot what the value was). The result is the travel rating for that fork which may not necessarily be the actual amount of travel that you experience while riding.

I used to keep a zip tie on one of my stanchions to measure sag, but I heard that the hard plastic can actually scratch the stanchion which can't be good.
 

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If the zip tie is pretty loose it can't be more damaging than debris flying up from someone else's bike and onto your stanchions, so I wouldn't worry about it.

A good way to measure travel is to ride in dusty terrain so that dust settles on the stanchions, you can then measure the distance from the seal to the "dust ring" and thus get the amount of travel you use.

Another great way is to find the model, make, and year of your fork and go to the manufacturer's website for info.

Which fork do you want to measure travel on?
 

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dude I have a "loose" zip tie on everyone of my forks. its the easiest way to see the max travel the fork has used on a trail or jump. and as for scratching the stans. well are you telling me that plastic is harder than alum. or steal? I dont think so, it might wear the anodizing but then the seals do that to so big deal. or even better if i could get a fork to last that long to acutally see wear that would be nice.

just put one on the stan. as said and let all the air out of the fork (if you can) and the fully compress it. then measure from the dust/dirt seal to the bottom of the zip tie. very easy and accurate
 

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Merkyworks said:
dude I have a "loose" zip tie on everyone of my forks. its the easiest way to see the max travel the fork has used on a trail or jump. and as for scratching the stans. well are you telling me that plastic is harder than alum. or steal? I dont think so, it might wear the anodizing but then the seals do that to so big deal. or even better if i could get a fork to last that long to acutally see wear that would be nice.

just put one on the stan. as said and let all the air out of the fork (if you can) and the fully compress it. then measure from the dust/dirt seal to the bottom of the zip tie. very easy and accurate
Think about it. Those plastic coated brake/gear cables that rub against your frame can eat a hole right through it.

The suggestion was to put an old o-ring on there the next time you take the fork apart as they are much softer.
 

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Hmmm, I had a zip tie on my Marzocchi fork for over a year - look mah, no wear!

Like I said, leave it a little loose and it won't hurt. Once you have worked out how much travel you are getting, cut it off if you are worried.

Snaky 69 also mentioned having a look after a ride in dusty terrin - works too.
 

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Discussion Starter · #8 ·
I meabt how the manufacturer sais this fork is 100mm or 80mm etc. Is it the measurment of the plush part (the part that "goes in") on the fork? Thanks.
 

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Markleo said:
I meabt how the manufacturer sais this fork is 100mm or 80mm etc. Is it the measurment of the plush part (the part that "goes in") on the fork? Thanks.
It has more to due with the distance between the crown race and axel when uncompressed. The actual "part that goes in" will be a little different for every 80mm fork out there but the distance from crown race to axel will be the same for all 80mm forks.

This is how and why the frame manufacturers are able to design a frame for a specified XXmm travel fork. What they are really saying is that the bike is designed for a fork with a particular overall length. If you deviate from that recommended length, the handling of the bike will be affected.
 

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BraveHeart said:
It has more to due with the distance between the crown race and axel when uncompressed. The actual "part that goes in" will be a little different for every 80mm fork out there but the distance from crown race to axel will be the same for all 80mm forks.

This is how and why the frame manufacturers are able to design a frame for a specified XXmm travel fork. What they are really saying is that the bike is designed for a fork with a particular overall length. If you deviate from that recommended length, the handling of the bike will be affected.
You are not correct.

Many forks with the same amount of travel have different axle to crown heights due to the crowns, exposed stanchion, drop-out configuration and all. The 80mm is nothing more than a general recommendation to make sure the bike handles like it's meant to. 80mm of travel means exactly that, when fully compressed, the fork will have traveled 80mm. Which means the exposed part of the stanchion will be 80mm shorter and the fork will have an 80mm shorter axle to crown height etc.
 

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snaky69 said:
You are not correct.

Many forks with the same amount of travel have different axle to crown heights due to the crowns, exposed stanchion, drop-out configuration and all. The 80mm is nothing more than a general recommendation to make sure the bike handles like it's meant to. 80mm of travel means exactly that, when fully compressed, the fork will have traveled 80mm. Which means the exposed part of the stanchion will be 80mm shorter and the fork will have an 80mm shorter axle to crown height etc.
If that were true than frame manufacturers would have to suggest a crown to axle spec to match a fork to their frame, which they do not. Only the travel. Its a lot more than a general recommendation, it has to do how the bike sits in the neutral postition.

If you put a 100mm fork on a bike spec'd for 80mm, you are raising the front of the bike which will slow steering and cause wheelies on climbs. The same would happen if different manufacturers used different crown to axel lengths for an 80mm fork.
 

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BraveHeart said:
If that were true than frame manufacturers would have to suggest a crown to axle spec to match a fork to their frame, which they do not. Only the travel. Its a lot more than a general recommendation, it has to do how the bike sits in the neutral postition.

If you put a 100mm fork on a bike spec'd for 80mm, you are raising the front of the bike which will slow steering and cause wheelies on climbs. The same would happen if different manufacturers used different crown to axel lengths for an 80mm fork.
A 100mm Manitou gold label has a 475mm axle to crown height. A rock shox pike at 100mm will have a 470mm axle to crown height, a marzocchi dirt jumper('06 and later) at 100mm will have a 486mm axle to crown height, a rock shox argyle at 100mm will have a 491mm axle to crown height(a difference of 21mm or almost an inch, that is almost 1 degree in head angle difference compared to a gold label). I used dirt jumping forks as an example as those are the forks I know best, but this goes for any and all forks.

As you can see, no fork with the same amount of travel has the same axle to crown height unless it comes from the same manufacturer, get your facts straight. Frame manufacturers design a frame according to a certain axle to crown height, and usually a bike using a fork within plus or minus 15-20mm of that will handle the same way it should. Also, usually, the manufacturers assume that most forks in the same travel as the fork they designed the bike around have approximately the same axle-to-crown height.

The '04 and '05 marzocchi 888's we're insanely tall and choppered out bikes and made them handle like pigs, and people complained that they were the tallest 200mm fork out there. Marzocchi redesigned their crowns so that the axle to crown height was nearly 25mm shorter, and guess what, they are still at 8 inches of travel(200mm).

I'm not trying to bash on you but to make you better informed, I hope I didn't come off as harsh.
 

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snaky69 said:
A 100mm Manitou gold label has a 475mm axle to crown height. A rock shox pike at 100mm will have a 470mm axle to crown height, a marzocchi dirt jumper('06 and later) at 100mm will have a 486mm axle to crown height, a rock shox argyle at 100mm will have a 491mm axle to crown height(a difference of 21mm or almost an inch, that is almost 1 degree in head angle difference compared to a gold label). I used dirt jumping forks as an example as those are the forks I know best, but this goes for any and all forks.

As you can see, no fork with the same amount of travel has the same axle to crown height unless it comes from the same manufacturer, get your facts straight. Frame manufacturers design a frame according to a certain axle to crown height, and usually a bike using a fork within plus or minus 15-20mm of that will handle the same way it should. Also, usually, the manufacturers assume that most forks in the same travel as the fork they designed the bike around have approximately the same axle-to-crown height.

The '04 and '05 marzocchi 888's we're insanely tall and choppered out bikes and made them handle like pigs, and people complained that they were the tallest 200mm fork out there. Marzocchi redesigned their crowns so that the axle to crown height was nearly 25mm shorter, and guess what, they are still at 8 inches of travel(200mm).

I'm not trying to bash on you but to make you better informed, I hope I didn't come off as harsh.
Not harsh at all snaky69. I can't dispute your numbers since manufacturers don't seem to publish them. Plus or Minus 15-20 seems a little steep though, and people would complain as they did in the case of the 888, and rightly so. What you are effectively saying is that there are some 80mm forks that are taller than some 100mm forks on the market, I can't honestly say that I would buy that.

On another note, of all the forks you mentioned, which I assume you own, do they really travel 100mm or is there some variation there also?
 

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BraveHeart said:
Not harsh at all snaky69. I can't dispute your numbers since manufacturers don't seem to publish them. Plus or Minus 15-20 seems a little steep though, and people would complain as they did in the case of the 888, and rightly so. What you are effectively saying is that there are some 80mm forks that are taller than some 100mm forks on the market, I can't honestly say that I would buy that.

On another note, of all the forks you mentioned, which I assume you own, do they really travel 100mm or is there some variation there also?
I own a dirt jumper and will soon own a Slammed Nemesis Project Z1. I have some time on a pike, the other forks I have mostly seen or parking lot tested but no more.

As far as your statement saying some 80mm forks are taller than some 100mm fork, it is sad but true. The '05 66RC used to be taller than any other fork(including dual crowns) out there when it came out(except maybe the 888) and it only had 170mm of travel whereas the dual crowns had 200mm. Scary eh?

They are meant to travel 100mm. Do they all travel exactly 100mm? Probably not. Depending on the manufacturing tolerances, bushing wear, spring(be it firm or soft), oil viscosity, oil level, compression settings, bottom out bumpers, rider weight etc, it will or will not travel it's full 100mm(or sometimes a tad bit more, rock shox seems to give error margins for travel on some of their forks on their website). A lot of things come into play when a fork compresses. I'd say most of them make it to 100mm(or pretty damn close) some way or another.
 
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