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Discussion Starter · #1 ·
I've got to cut down my new Thomson Elite post to fit my RM Switch I'm building up. I've got access to a hacksaw and a mitre box (wooden box with slots in it that help you cut straight). Basically I'm wondering if anyone has any tips or if i just saw it and then??? file it smooth???

Also my seatpost is meant for 7mm rails and my seat has 8mm rails. I was gonna return it but I emailed L.H. Thomson and they said it would work fine. The rails don't sit perfectly in the grooves since the 8mm rails have a more gradual curve but it seems to hold fine. Does anyone think using this post is a bad idea and I should return it for a 8mm specific one?
 

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if thomson said it wold be fine, then i would use it. if all you have is a hack saw, cut it and file it smooth, no problem. if you have acess to a pipe or tubing cutter, it will be a cleaner cut, but since its going down inside your bike anyway, i guess it dosen't matter...
 

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SHIVER ME TIMBERS said:
yep...pipe cutters are better but a hacksaw will do...just remember to sand off all burrs
Thomson states "do not use a pipe cutter". If it must be cut use a hacksaw.

The reason for this appears to be the fact that the post is thicker in the front and back. I have cut several without problems (measure twice, look once. Measure twice again, then cut. those are expensive).

Tiggerr
 

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Tiggerr said:
Thomson states "do not use a pipe cutter". If it must be cut use a hacksaw.

The reason for this appears to be the fact that the post is thicker in the front and back. I have cut several without problems (measure twice, look once. Measure twice again, then cut. those are expensive).

Tiggerr
Yeah, I second that. Thompson's are a little tougher (but not impossible) to cut with a pipe cutter because the inside is ovalized.
 

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Who are the brain police?
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Start w/ pipe cutter & end with hacksaw. ..The pipe cutter gives you a perfect cutting guide.
 

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Discussion Starter · #7 ·
Thanks for the info. I'll use the post and I guess a hacksaw to cut it. The cut will be visable as the RM Switch has an interrupted seat tube so it's too bad I can't use a pipe cutter but I don't easily have access to one and I would need to be careful with the wierd thomson wall thickness variations.
 

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Tiggerr said:
Thomson states "do not use a pipe cutter". If it must be cut use a hacksaw.

The reason for this appears to be the fact that the post is thicker in the front and back. I have cut several without problems (measure twice, look once. Measure twice again, then cut. those are expensive).

Tiggerr
Use a hoseclamp as a hacksaw guide. My LBS gave me that tip for cutting handlebars and seatposts. Measure/mark the length you want, clamp the hoseclamp on next to the mark, cut along it (since it's steel the saw will slide along the edge). You still need to file/sand the burrs off, but the cut will be straight.
 

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Discussion Starter · #9 ·
Ok, sounds good...any tips on painting it black? Thomson posts are so sexy it'd be a shame to have a nasty scraped up silver/black bottom on my black post. Do you guys think touching it up with modeling paint is a good idea or do you think because it's anodized (I think)(sp?) the paint will look like crap?
 

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Paint won't hold.

A nice clean cut (hoseclamp idea is good), and it will just look like a shorter post..
 

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paint???

After your first ride and you get dirt on it, it won't even matter.

If you want it to look perfect for your first ride though, use a black Sharpie permanent marker to cover the end where you cut it.

Hose clamp is a great idea--I have to cut my Thompson tonight too and will give it a try
 

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Discussion Starter · #12 ·
The only problem that I can see with the hose clamp idea is that I want to cut it at an angle. The bottom of my seatpost tube is at an angle and I'd like to match that with the cut. That way I can have the seatpost a bit longer on the one side. If I were to have it too long then the shock would hit the back of the post first as it's on a pretty steep angle at that point...Maybe I'm just being anal.

Anyways, here's a link to a pic of my frame so you guys can give your 0.02$ as to whether I should angle cut it or not. I do have a mitre box that is used for cutting wood on an angle and I think it would work ok for this too.
http://www.bikes.com/bikes/bikeZoom.aspx?f=/bikes/2003/zoom/images/switchltd_detail.jpg

Here's a link to a pic of a mitre box (mine has a few more angles than this one) so you know what I'm talking about:
http://www.tool-up.co.uk/shop/diy/EMI2259.html

My shock is in the mail on it's way back from Push Industries right now so I won't be riding till tue/wednesday anyways so I'm in no hurry. I might even go buy/borrow a pipe cutter if that hack saw really looks messy.

Last Question (I promise!): Should I cut my post so short that if I slam it all the way down and then bottom out the suspension I'm still ok? If I do this it'll be pretty short for the odd XC ride I do. I could leave it a few inches longer but then I'd have to remember not to slam it too low....opinions??
 

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if you do want to cut it at an angle, you will not be able to use a pipe cutter and you will want to be extreemly careful to cut the angle exactly level. yo will probably also want to clamp the post down before cutting it, as it will tend to rotate when starting the cut with a hack saw (makign it harder to get the angle perfedctly level. i personally would not cut it at an angle. before you cut the tomson though, have you considerd a telescoping tube (i think titec makes one)? that would allow you to have a far greater range of adjustability for those occasional xc rides and still keep the tube out of the way of the shock.
 

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Discussion Starter · #14 ·
I've heard so many good things about the Titec telescoping posts and in hindsight it makes a lot of sense. I ordered my post off the web so to return it would be a big hassle and $$$ for shipping. I got the Thomson one cuz it's so sexy and it's super strong. I won't be way shorter than I need either...just a bit. I think I'm just gonna:
- Cut it straight
- Cut it short enough I don't have to worry about demo-ing my shock
- Thus, Suck it up on the XC rides
- Try and find pipe cutters and then I won't need the clamp...maybe do 1/2 and 1/2 with pc's/hacksaw
- Try the sharpie to get it all black.

Thanks for all the info!
 

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Warp speed, Mr. Sulu!
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For what it's worth...

I'll give you my $0.02 on it.

Seeing that you live in Ontario, as do I, I think that you will be doing more XC type riding on this bike than you might have originally thought, unless you plan to reserve this bike for Blue Mountain rides only.

Because of this, I would suggest cutting your post a little longer than you think you really want it and try it that way for a while. If you find you can live with it that way when you get to more downhill type stuff, you haven't completely sacrificed pedaling efficiency for your XC rides.

Remember that the bottom of the seat tube is not very likely to be able to touch your shock's spring at it's most compressed position, so you could leave the seat post a little longer than that. Take the spring off the shock and compress the suspension with just the shock installed (no spring) to see how close it will get.

Lastly, if you do go for the Titec telescoping post, realize that you will have to cut this one as well. I have one of these, and to give myself the optimal height for both XC and downhill riding, I needed to cut both the inner and outer tubes of the post. It's a bit tricky because you have to ensure that you are leaving the required mimimum length of insertion for each tube of the post.

You won't likely have any trouble selling your Thompson post if you decide to go with the Titec, and provided you got a good deal on it in the first place, you can probably get most or all of your money back.
 

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Discussion Starter · #16 ·
I did get it for a pretty good price (59$ US) so I could sell it although my size is 26.8mm and I think that's more of a rare size (I could be wrong).

Pucker Factor: I know what you mean about Ontario being kinda lame for freeriding. There are a few spots (Blue Mtn, Kelso etc) and there used to be more. In the Kitchener/Waterloo area we had two awesome trails with a ton on N.S style stunts called Technical Ecstasy and "The Hydro Cut" but both were torn down shortly after I started riding. Other than a few secret DJ spots all my riding has been Urban freeriding. I switched to a hardtail (Kona Roast) because of this 2 years ago and it's done wonders for my skills but I really miss a full squish bike for big stair gaps and 5-7 footers to flat. Mostly I'm going to be using this bike for urban freeride sessions and just toolin around on my way to University etc. which is why the seatpost height isn't a huge deal.

With all that said, I have been trying to make my bike as XC friendly as possible through the choice of light yet strong components (ie SRAM PC99 Hollowpin Chain, SRAM 990 11-32T cassette, Marz Z1 Fr1 fork instead of a 66RC etc. and by sending my shock to Push Industries. I've also got really fast rolling tires (Maxxis Holy Rollers) that'll rock for both urban and packed XC trails. When I get my shock back from Push next week I'll see how long I can make my post before it hits and if that height will be ok. If not I'll have to decide between having a crappy seat height on XC rides and buying the Titec post. I haven't actually been XC riding for about 2 years but I imagine as I get older (I'm 21 now) I'll get wussier and do a bit more XC.
 

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SHIVER ME TIMBERS said:
yep...pipe cutters are better but a hacksaw will do...just remember to sand off all burrs

8mm will be fine
No no no..............

I thought the same thing until I read the Thomson manual......it said NO pipe cutters.....use a hacksaw.

Then use a file and emory cloth to take off the burrs.
 

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Warp speed, Mr. Sulu!
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It looks like your situation is a bit different than mine. I don't ride any pavement with my bike, and mine's a heavy pig, (45 lbs.) so I need all the pedaling efficiency I can get. :D

I just got my big bike late last fall, and once I cut the post short enough to be able to get it to a "downhill" length, I was shocked at how much harder it is to pedal.

Yes, 26.8 mm is a bit of a rare size. Actually, I wonder if you could even buy the Titec post in that diameter?

Well, I guess you are the only one that can decide what's right for you. You can always take more off if you cut it longer than you think it should be.

Good luck!
 

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Discussion Starter · #19 ·
Pucker Factor: Other than Blue Mtn. where do you ride in Ontario? Any cool freeride trails would be awesome to know about as would your favorite DH runs. You can PM me if you don't wanna post on here.
 

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Discussion Starter · #20 ·
What's an Emory Cloth?? I guess I'll try either the mitre box or the clamp with the hacksaw but I still might start it with some pipe cutters just to get a bit of a guide groove and possibly a cleaner cut. I've cut quite a bit of stuff with pipe cutters so I have a decent idea of how carefully to proceed.
 
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