Trek Singletrack 950 seatpost/clamp replacement
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Trek Singletrack 950 seatpost/clamp replacement
Bought this bike at the bike swap meet. Probably a dumb question but.... I have added a new front wheel that it was missing, but it is also missing the Seat post and a clamp to secure the seat. I tried a post from a similar era trek I have, and it fit. I measured the diameter, it seems to be exactly 1 inch. Does that sound right? There is no way to secure the post on the bike, nor is there a place to put a bolt on the frame. There is a line cut into the frame near where the seat goes in that is about one inch long or so. What do I get to secure it with. Obviously, I don’t know much about bike mechanics, so this is all new to me. Thanks
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I would be surprised if either the post or the seat tube has an OD of 25.4mm (1"). Seat post fit is pretty specific and frame damage can happen if the wrong size is used. I strongly suggest that you seek out help from someone who can confirm the post you have is the best fit for your bike. As to the clamp aspect you'll need to get a separate seat tube clamp with it's own bolt. The seat tube top's OD will be the clamp's ID. Measuring with a common ruler won't give you a fine enough gradation to discover the tenths of a MM that can make it fit properly or not.
Not knowing where you are makes it hard for us to do much more but suggest a visit to a LBS. If you have one nearby they should be fluent in these things. Of course the right thing to do when a store supplies you with information is to buy the part from them. Posts and clamps are fairly cheap compared to a damaged frame. Andy
Not knowing where you are makes it hard for us to do much more but suggest a visit to a LBS. If you have one nearby they should be fluent in these things. Of course the right thing to do when a store supplies you with information is to buy the part from them. Posts and clamps are fairly cheap compared to a damaged frame. Andy
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If you don't already have one, Harbor Freight will sell you a decent digital micrometer for $19. Get an accurate measurement of the inner and outer diameters of your seat tube to determine the correct seat post and seat tube clamp. These things are sometimes on special offer (I bought mine for ~$10) - in terms of general usefulness, worth their weight in gold.
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[QUOTE=wclarkin;20853150I measured the diameter, it seems to be exactly 1 inch. Does that sound right? There is no way to secure the post on the bike, nor is there a place to put a bolt on the frame.[/QUOTE]
Maybe, maybe not, you need to work in metric, apart from the headset, and a couple of threads, everything on a bike is measured in metric (getting a caliper is a godo sgestioin, you will find lots of use for it on bikes).
The Singletrack 950 was made for 7 model years, 1993-1998 (missing 1997) https://www.bikepedia.com/Year.aspx?search=trek%20950 and going on the specs of the 1994 model, it needs a 27.2mm seatpost, given that the frame is steel, it's unlikely that the diameter changed over the production run. (see page 45) https://www.vintage-trek.com/Trek-Fis...manualTrek.pdf
The way to secure the seatpost, you need a seat collar, this will be of a larger diameter than the seatpost, go to any good LBS, and you can get generic ones, or if you want something a little nice, maybe look at Thomson/Salsa as in the link above.
Good luck with the 950, they were nice bikes BITD, pretty sure they were some of the last made in Wisconsin steel frames Trek did.
Maybe, maybe not, you need to work in metric, apart from the headset, and a couple of threads, everything on a bike is measured in metric (getting a caliper is a godo sgestioin, you will find lots of use for it on bikes).
The Singletrack 950 was made for 7 model years, 1993-1998 (missing 1997) https://www.bikepedia.com/Year.aspx?search=trek%20950 and going on the specs of the 1994 model, it needs a 27.2mm seatpost, given that the frame is steel, it's unlikely that the diameter changed over the production run. (see page 45) https://www.vintage-trek.com/Trek-Fis...manualTrek.pdf
The way to secure the seatpost, you need a seat collar, this will be of a larger diameter than the seatpost, go to any good LBS, and you can get generic ones, or if you want something a little nice, maybe look at Thomson/Salsa as in the link above.
Good luck with the 950, they were nice bikes BITD, pretty sure they were some of the last made in Wisconsin steel frames Trek did.
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Maybe, maybe not, you need to work in metric, apart from the headset, and a couple of threads, everything on a bike is measured in metric (getting a caliper is a godo sgestioin, you will find lots of use for it on bikes).
The Singletrack 950 was made for 7 model years, 1993-1998 (missing 1997) https://www.bikepedia.com/Year.aspx?search=trek%20950 and going on the specs of the 1994 model, it needs a 27.2mm seatpost, given that the frame is steel, it's unlikely that the diameter changed over the production run. (see page 45) https://www.vintage-trek.com/Trek-Fis...manualTrek.pdf
The way to secure the seatpost, you need a seat collar, this will be of a larger diameter than the seatpost, go to any good LBS, and you can get generic ones, or if you want something a little nice, maybe look at Thomson/Salsa as in the link above.
Good luck with the 950, they were nice bikes BITD, pretty sure they were some of the last made in Wisconsin steel frames Trek did.
The Singletrack 950 was made for 7 model years, 1993-1998 (missing 1997) https://www.bikepedia.com/Year.aspx?search=trek%20950 and going on the specs of the 1994 model, it needs a 27.2mm seatpost, given that the frame is steel, it's unlikely that the diameter changed over the production run. (see page 45) https://www.vintage-trek.com/Trek-Fis...manualTrek.pdf
The way to secure the seatpost, you need a seat collar, this will be of a larger diameter than the seatpost, go to any good LBS, and you can get generic ones, or if you want something a little nice, maybe look at Thomson/Salsa as in the link above.
Good luck with the 950, they were nice bikes BITD, pretty sure they were some of the last made in Wisconsin steel frames Trek did.
Thank you all so much! I will try that diameter of posts and hope for the best, can always keep it for another bike down the road. Is there a certain amount the collar should be larger than the seatpost in general? Thanks
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Sorry for repeating the measure bit, but this is key not just for this part, but many parts on bikes, if the collar/clamp is too small, it will have to be forced over the seat tube, as it's made from Alu, it could crack/bend, if it's too large, if it can be done up, again it could crack/bend, in both cases it's could result in damage to the seattube (would say could, a I picked up an old 1991 Kona MTB with a wrong size clamp, the clamp had to be scrapped, the seatpost a bit more scratched than it should have been, but the frame (top of the seattube) luckily wasn't crushed).
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Nice find!
I can assure that my Singletrack's seat post is 27.2. I'm not with the bike now, but I'll try to take a picture from that collar.
I can assure that my Singletrack's seat post is 27.2. I'm not with the bike now, but I'll try to take a picture from that collar.