Pace frames and shimmed seatposts

[rich_4130]

I've heard a lot about RC100's and early RC200's cracking around the seat clamp area when used with shimmed seatposts. From what model is it safe to use shims? I have an RC200 F2 which currently has a shimmed u.s.e. post, it doesn't get used much and has been fine so far but I don't want to risk it if it's wrong.

Cheers,
Rich.

 

[northerndave]

I'd be quite wary of using a shimmed post in most older aluminum frames, in the same way as using a seat post at close to it's minimum insertion depth.

Shims and riding with not much post in the frame means that the post is more likely to flex the frame as it's got less support.

The longer the extension of the seat tube above the toptube and stays the more as risk I'd say the frame is because the tube extension probably also try's to flex, so Kleins and Early RC100's are pretty problematic.

Having said that i've never had a frame break from a shimmed post but heard a bout a few people who have.

 

[tintin40]

I've used shimmed post in allu frames and never had a problem. SO i think it depends on many things such as type of rider you are. size of frame/length of post/length of shim. Oh and weight of rider all come in to consideration.
May be different for Pace?

 

[Jason802]

No point taking a chance, just change it. I personally like shimmed posts in hardtails as the extra flex softens the ride a little.

I have a non-shimmed Easton carbon in my Rocky Mountain Blizzard, it's got almost an inch of rear-ward flex making it almost a soft-tail :shock:

 

[mikee]

not a good idea with a pace
you can get 29.4 dia posts 400mm long from this guy on the bay

muddycycles-online-since-2001

for less than a tenner
okay its not a syncros ,but it might not break your frame

 

[Jason802]

This one looks tasty and cheap, a copy of something exotic no doubt. 350mm length, 100mm minimum insertion

http://cgi.ebay.co.uk/New-Bike-Alloy-20 ... 53de78b7bd

 

[northerndave]

I picked up a nice FSA post in 29.4 for about £15 a while ago for my Fat Chance from CRC. Not sure if they still have em.

 

[rich_4130]

Thanks for all your input. My old F2 has a 27.0 seatpost which is a bit harder to come by. Also, don't want to appear snobbish, but this was alway my dream bike when I was younger so I'm looking to keep it equipped quite nicley. Will look out for a Syncros or similar.

Cheers,
Rich.

 

[ashsmith]

Why don't you get a 27.2mm turned down?

 

[retroklein]

I've heard a lot about RC100's and early RC200's cracking around the seat clamp area when used with shimmed seatposts. From what model is it safe to use shims? I have an RC200 F2 which currently has a shimmed u.s.e. post, it doesn't get used much and has been fine so far but I don't want to risk it if it's wrong.

Cheers,
Rich.

I think all the old USE posts came with shims, it was the shim that came in different widths for different frames, the problem with the early ones the shim was not long enough to give good support inside the frame. You could try getting a new longer shim that goes past the bottom of the post, a friend of mine made his and is still riding it now or like others said, a proper width post... but unless you're a heavy rider you should be fine ...