Steerer length query?

[KWICKS]

Hi,

Noobish question but I think others may benefit from a good answer...

Can someone with decent knowledge explain what I need to know to buy forks with regards to steerer length. Why do lenghts vary? Do lengths vary for the one frame or only between different frames? Or different typres of frames, eg DH vs XC? I have a Giant Talon and I've seen some forks for sale that are of interest but how should I know they will be right?

I did a search and only came up with for sale threads with questions about what steerer length a particular item was. I need to know what to do with the information supplied for this steerer length.

 

[Zoobz]

Generally most forks will fit on most bikes.
If you are looking to buy a new pair of forks, i'd suggest thinking of what their intended use would be. For your Giant Talon, anything more than 100-120mm travel would start to affect the geometry of your bike (and you VOID you warranty on the frame). Most steer tubes are cut between 180-220mm. As long as the steer tube size is 1&1/8th of an inch it will fit on your bike. I know my mates Giant Alias was cut to about 210mm from factory.

If a steer tube is too short you could always take out your spacers, if it is too long you can always add spacers, but you should always still feel comfprtable on the bike. Most bikes from factory ahave more than an inch of spacers on them anyway, so it gives you some room to play with.

I'n just a newb myself, i hope this helps. Maybe someone else can shed some more light on the situation.
I'd suggest pulling out your forks to measure the steer tube proberly, its not had and could save you some hassel later on.

 

[StInKy LoVeR]

Hey,

Generally Downhill steerer tubes are longer? correct me if im wrong because of the need for a bigger/stronger headtube thus this makes the headtube on DH bikes longer. Might not pay any attention to what I just said thought. It just popped into my head. If the steerer tube is to short, you have two options. You could sent it to grip. He does steerer tube extensions whitch he guarentees strength. Or you could call up your LBS, I asked mine to order in a marzachochi (sp) steerer tube. Once they got it sent in they then pressed the steerer tube in for me to. The prices of steerer tubes can vary. I was looking on chain reaction and a steerer tube for my 888 was around $100-$120 australian. So if you can avoid it try and buy the right sized steerer tube.

 

[AngoXC]

Steerer lengths on forks will be different across the board.
You have to take into consideration a number of things, the first being the height of your headtube, the second being your 'stack height' (ie. the space your headset cups takes up vericially), the option of spacers and finally, the overal 'height' of the stem.

From factory (either a brand new fork or one fitted to a brand new bike) will usually have an uncut length of 200mm or more. (Note that your Talon will have a series of spacers under the stem to counter this). Depending on your frame size and stem configuration, you should be able to go as low as 175mm with no spacers, comfortably. Again, check the 'stack height' of everything if your not sure and dont be affraid to loose spacers! You also need to factor in the headset adjustment (ie. the steerer needs come just a few mm short of the top of the stem to allow for the top cap to 'pull' the steerer into the headset, hence , 'preloading' the bearings.)

For XC, it is preferable to have a reaosnably low front end for handling and climbing ability...such that many XCers run no spacers and flip their stems to achieve this. Likewise, DHers also like a lower front end but have to deal with larger headtubes, taller stems and the likes so steerers will be longer on such bikes BUT you have to then consider the use of direct mount stems which will result in an even lower steerer tube length. This only applies to triple clamp-style forks though with an upper crown.

Asside from some dual crown forks where the steerer can be removed from the crown, steerers are all press-fitted into the crown and cannot be removed without weakening the materials each is made from. So its good to get it right the first time

Just a few more points I guess...good luck!

 

[Tazed]

There's a difference between steerers found on OEM (original equipment manufacturer) bikes and those bought aftermarket (in your LBS).
There's often differences in the internals, too, but lets look just at steerers.
When a manufacturer negotiates, say, 10,000 forks for a product run, they will also work out exactly how much steerer they need for those models.
Even a 10mm difference in length brings a reduction in fork price (the forks are manufactured specifically for that order), as you're using less material.
So there's no real standard when considering OEM bikes.
Aftermarket is different.
The new fork in your LBS (if not removed from a bike...) will have a long steerer. Easily 200mm plus.
This is because it has been made to fit any bike (at least, bikes the fork should be put on!) and head tube lengths/headset stack heights vary greatly, so they need to cover all conceivable options (within reason).
And you pay for that, so it's OK.
Finally, when buying 2nd hand, you need to know the steerer length, as mentioned above.
You can measure your current fork/headtube/headset (or just drop the fork out and measure the steerer) to get the same length or work out the minimum.
I bought a 2nd hand fork a few weeks back. I calculated the steerer as being about 10mm longer than the bare minimum I had with frame/headset/stem.
However, I put in a headset with a greater stack height, and now I only have about 3mm over.
Perfect in this case, but you cans see how quickly it can change with shorter steerers!

 

[zen zen]

noob question

another noob question

how do you measure your steerer tube without taking it off the bike?

 

[Zoobz]

another noob question

how do you measure your steerer tube without taking it off the bike?

you wont be able to do it too accurately in one go so i'd suggest...

1) Find out the stacked height if you headset +
2) length of you head tubde +
3) stacked height of spacers +
4) height of stem minus 2-5mm off the stem

that should give you a pretty accurate measurement...but i'd highly recommend taking of your forks. It doesnt take that long...

 

[Pebble]

Plenty of good info so far for you.

I think that if you plan on having the same set up (stem, spacers etc) then you could do a rough measurement - just measure from the bottom of your headset to the top cap on the stem. That will give you a rough steerer length you're looking for. But like others have said it is easy enough to take the fork out for an accurate measurement (just read up on it because the stem and top cap bolt should be done up in a certain order when you put it all back together).

Something else you might want to consider is weather the fork you're buying comes with a star nut already installed (most used ones will), otherwise it's something else to add to your list. And don't forget to take the crown race off your old fork (it should stay with your headset and be installed on the new fork), it's generally the silver ring that sits at the base of the steerer tube.