[mandown]

i have a bur in the seattube of my transition bottlerocket. i have had two shops try to finish the tube, but the tool they are using does not have enough reach to get the job done. i looked down the tube with a flashlight and can't seem to see anything that would cause a scratch in my seatpost, yet my seatpost is scratched and does not slide easily. any suggestions?

 

[zebrahum]

did the shop use a reamer or a honer? Neither can reach very far into the seat tube, but the reamer will physically cut material out of the way. If they just used a ball honer (usually attached to a power drill) then it wouldn't knock down any really agro sharp spot. If it's below the reach of the reamer, it's not going to be easy to get to. Maybe a file taped to a stick?

 

[ridefast]

the ball hone that we use is almost a foot long from the tip to then beginning of the drill chuck

does your seatpost really need to be that long? im only assuming that the hone your shop uses is similar to ours

 

[mandown]

i think they used a ball hone. i'm not sure what the tool is called, but that description seems most likely based on what i saw of the tool.

from what i can tell, the bur is about 12 inches down. i did not measure it, but that is roughly the amount of seat post insertion that goes freely. after that, it gets rough. it appears there may be a popcorn weld for the FD braze-on.

i do need that much seat post. i bought this frame because i knew i could get full leg extension with it if i ran a full length thomson seatpost, and i could slam the seat down to a height i am comfortable with (i like 'em low).

it sounds like i need to get a reamer. however, since i cannot see the bur, i may just need a hone with an extension. hmmm....

 

[ridefast]

yea, i forgot about the possibility of needing a super long post with that frame

i think your best bet will be finding the extension like you said....try contacting a performance automotive engine shop if you cannot find a longer reach ball hone elsewhere....they have some funky, long reach hones like that sometimes

 

[mandown]

that is a great idea. i'm so bike focused that i often forget about auto and moto shops.

 

[davep]

I picked up a cheap cylinder hone a while ago to do this at home (I NEVER let a shop work on my bikes). They are quite a bit cheaper than a ball hone and do essentially the same thing for personal use.

For your specific issue, there are flexable/non flexable extensions that will work for either type of hone.

 

[mandown]

where did you acquire it?

 

[zebrahum]

if it's a weld and not some extra paint or rough surface, a honer probably won't fix the problem. You'll still need to ream it.

 

[davep]

where did you acquire it?

If you are asking me, I got it at an auto parts store. Google 'brake cylinder hone'. I have a 3 stone one, it was less than $10. An extra long one might take some digging, although an extension is easily had. You could even use a drill bit extension ($5 at a hardware store).

 

[mandown]

thanks dave!

 

[chober]

I had a burr in my seattube too, first insert got a couple squiggly lines running down the back of my 410mm thomson now.

 

[chober]

Mine was near the top at the cut in the tube, so a cylinder hone took care of it

 

[mandown]

interesting. mine was in the front. then i got some scratches on the side. i even got a few in the back. i have been trying to figure out if the problem is with the derial braze on, or if it is from the gusset welding. the gusset welding requires two holes to be drilled in the seat tube so they can weld the gusset on without making the frame explode from the expanding heat.

yesterday, a buddy with a medium frame started to get a scratch in his seat post. what the hell?

chober - if you are in pasadena, you are not far from me. do you have the cylinder hone you used? if not, where did you go to have your work done? i need that thing cleaned up. my seatpost is eaten alive.

 

[chober]

Saw his seatpost....oh man the whole lower 3rds of it was mangled ALL SILVER, and the post started off black.

 

[mandown]

chober is a good man for helping me out with my seat tube (wow, that sounds... odd). i think he fixed the problem with the three stone hone. his bike shop is damn fine too. H&S in Burbank - check it.