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Big Wheel Homer !!
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Discussion Starter · #1 · (Edited)
I'm having problems with my seatpost slipping down. I have a Thomson setback post and I'm using it on a Lenz Sport Leviathan. I've tried a QR seatpost clamp as well as a bolt on. I've tried it with grease, without grease and even with anti-seize lubricant. Basically the same results with all, drop of about 1/2" - 3/4" within a hour of riding.

Yesterday I decided to try a new carbon post I had in the parts bin. It's even worse than the Thomson. The carbon post has the scale printed on the post and I set it on "3". Within 15 minutes of riding the post had slipped to "8". On my ride last night it seemed I spent more time adjusting my post than riding.

Any ideas? Would a shim made out of a aluminum can work? Help!:madman:

Thanks,
Steve
 

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A shim should work, but as strange as it sounds you just may have the wrong size post. I know you probably got the size of the seat tube either from where you bought it, the frame mfr's website or from someone else, but it sounds like it's a couple tenths of a millimeter off.
 

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*Hotter than Hell*
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empleo papel

cruzthepug said:
I'm having problems with my seatpost slipping down.
Any ideas? Would a shim made out of a aluminum can work? Help!:madman:
Thanks,
Steve
Try a sheet of paper for a shim.:thumbsup:
 

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Don't Stop Spinnin'!
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QR clamps suck. Stick to the one you adjust with a allen key. Make sure you have a clamp that is the correct size for your seat tube. If you have one just one degree larger you might not be putting enough pressure on the post. Take it to your LBS and have them help you out.
 

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Big Wheel Homer !!
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Discussion Starter · #8 ·
Nat said:
Try rubbing either rock climbing or kids' sidewalk chalk on it. Seriously.
Nat, I'll give the chalk a try. I stopped on the way home from my ride this morning and bought a box. It's strange, I've had this frame for about a year and a half using the same seatpost and just in the last few months it has begun to slip. I'll let you know how the chalk works.

Steve
 

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I already rode that
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Try a Salsa seatclamp. Holds my Thomson in place alot better then the stock did as well as 2 others that failed too hold it in place. Mostly cause it uses that cam thingy so the bolt doesnt bend when tightened very tight. Im using the Q/R version though but Im sure the one without would work just as good.
 

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What worked for me.

I was having the same problem and what I ended up doing was making sure everything was clean and greased then made the clamp very tight, i.e. before I was making it so it took some force to close the clamp , but now I make it so I have to use quite a bit of force to close the clamp.

Good luck.
 

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NMBP
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Thomson on a Behemoth. I use 1/2 of a water bottle seat post mount to give the seat a place to stop. I have to take my seat off to fit in my truck, and my knees despise change. This also prevents the post from slipping.
 

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Fo' Bidniz in da haus
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ditto on the chalk....have used it on 2 problematic bikes and voila, no mas slipping. best part is that there are usually plenty of neighborhood kids you can beat up and take the chalk from
 

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Big Wheel Homer !!
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Discussion Starter · #13 ·
Nat said:
Try rubbing either rock climbing or kids' sidewalk chalk on it. Seriously.
DING, DING, DING, DING, DING, We have a winner. I've got in several rides now with no slippage. Great call on the sidewalk chalk Nat, thanks.

Steve
 

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cruzthepug said:
DING, DING, DING, DING, DING, We have a winner. I've got in several rides now with no slippage. Great call on the sidewalk chalk Nat, thanks.

Steve
Cool, man. Now if only I could get anyone to believe me about using WD40 to mount grips...
 

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Can't you just open the QR and tighten the allen wrench on the other side of the QR. Or at leat that what I did when I had to use a different seat and seatpost off a different bike.
 

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less is more
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I've purchaed 2 high-end bikes that had the wrong size post mounted. Off 0.2mm smaller. You wouldn't know until you try the right size & find it fits like a glove. Go to your bike's website & find out the correct size by emailing customer service.
 

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venus1 said:
I've purchaed 2 high-end bikes that had the wrong size post mounted. Off 0.2mm smaller. You wouldn't know until you try the right size & find it fits like a glove. Go to your bike's website & find out the correct size by emailing customer service.
All Lenzsports have a 27.2, but I think Steve knew that already.

Lenz's Customer Service Department! That's funny.
 

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Nat said:
All Lenzsports have a 27.2, but I think Steve knew that already.

Lenz's Customer Service Department! That's funny.
Is his seat post 27.2? He never said he checked what the post he was trying was. BTW, there is variance you know in 1/100ths even w/ those that say 27.2 on the end of the post. I know that from experience w/ several really nice posts.

Ok, tell me why that is funny?
 

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venus1 said:
Is his seat post 27.2? He never said he checked what the post he was trying was. BTW, there is variance you know in 1/100ths even w/ those that say 27.2 on the end of the post. I know that from experience w/ some nice posts.

Ok, tell me why that is funny?
Steve isn't a neophyte, that's why I figured he'd know enough to look at his seat tube size and buy the seatpost marked with the same dimension.

It's funny because Lenz Sport is a one-man operation. Devin handles all aspects, which is why the idea of his Customer Service Dept. made me chuckle. I didn't really expect you to know that, but Steve would've.
 
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