Shim for quill stem - ok to do or no?

[henrypretz]

Hi folks - I'm mostly a reader/lurker but I'll exit my cave to ask for some guidance.
I recently purchased a Burley Rock n' Roll tandem that sports a 1 1/8" threaded fork. I have a Nitto Periscopa stem that is made to use with a 1" threaded fork. I know that some threadless adapters (http://www.amazon.com/gp/product/B000FGYKY6/ref=pd_lpo_k2_dp_sr_1?pf_rd_p=486539851&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B000WYEIW0&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=0K4NWG291S15SE5C1CWA) come with a shim that will accommodate this, but just because you can do it doesn't mean that you should. If the consensus is, yes, this is safe, then I'm off to classifieds to look for the shim alone, or buy an adapter just to get the shim. If not, then I'll go ahead and move on to something else. Any input is greatly appreciated.
BTW, I learn a lot just by hanging out here on the boards. This is a fun and very knowledgeable group.
Thank you,
Henry

[eddief]

really that your tandem has a 1.125 THREADED fork? sort of unusual, but I know Chris King makes a 1.125 threaded headset.

your link to the adapter makes me wonder if the included shim is actually for using a 1 inch or 1.125 inch THREADLESS stem rather being able to stick the adapter in either a 1 inch or 1.25 fork.

and a Nitto Periscopa, to the best of my knowledge, is a quill stem, so your questions are confusing.

do you want to use a quill stem or a threadless stem? as far as I know there is not an adapter that would allow you stick a quill stem in a 1.125 threaded (or threadless) fork.

maybe more info would be helpful.

[henrypretz]

Hey, thanks for the reply. Sorry if I was unclear. Yes, it is a 1.125 threaded fork (running a Chris King headset). I am looking to use the Nitto, a 1" quill stem, in the fork, which uses a 1.125 quill stem.
The adapter that I linked to was just to show that a shim does exist. It enables use of the adapter (which is made to be used in a 1" threaded) in a 1.125" threaded fork to adapt to 1.125 threadless stem, I think?

If I didn't mix you up before, I think this should muddle things sufficiently :)

[eddief]

the shim that comes with that adapter is not to stick into the fork, but rather to make the adapter work with either 1 inch or 1.125 inch threadless stems. in other words that shim goes on the top of the adapter where the stem is mounted. I have never seen a shim you put into the fork to make the diameter of the fork smaller.

[bobswire]

Hey, thanks for the reply. Sorry if I was unclear. Yes, it is a 1.125 threaded fork (running a Chris King headset). I am looking to use the Nitto, a 1" quill stem, in the fork, which uses a 1.125 quill stem.
The adapter that I linked to was just to show that a shim does exist. It enables use of the adapter (which is made to be used in a 1" threaded) in a 1.125" threaded fork to adapt to 1.125 threadless stem, I think?

If I didn't mix you up before, I think this should muddle things sufficiently :)

The shim is made so you can use either a 1" or 1.25 " stem NOT to be used for the inside of the the fork tube.
You will need to use a 1.25 quill stem or quill stem adapter and find a stem with a rise that suits your needs.

[eddief]

this appears to go into your size fork and then a threaless stem on top of this:

http://aebike.com/product/profile-conversion-25.4mm-1-1-8-fork-to-28.6mm-1-1-8-threadless-stem-sku-sm6402-qc30.htm

[oliver1850]

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[Beeb]

Isn't the issue here the diameter of the quill? A 1" threaded headtube bike takes a 22.2mm quill stem. I'm not sure what diameter stem a 1.125" headtube would take, but it wouldn't be 1.125. You should check and make sure the interior dimension of the steerer tube isn't in fact sized for a normal 22.2mm stem. It makes sense to me that a tandem would use a beefier steerer. Might be worth a trip to the Tandem list archive on search.bikelist.org to see if anyone has had this issue there. Agreed with bobswire that the nitto shim is so you can use a 1" OR 1 1/8" threadless on your adapter.

Shimming inside the steerer tube sounds like a really bad idea.

[Beeb]

Re-reading, tt sounds like the quill stems sized for 1 1/8" MTB steerers would be the way to go. And plenty of 25.4 road bars are available. Nitto makes a wide variety.

[RPS]

If the consensus is, yes, this is safe, then I'm off to classifieds to look for the shim alone, or buy an adapter just to get the shim. If not, then I'll go ahead and move on to something else. Any input is greatly appreciated.
Henry, it’s an interesting question and one outside of the norm. I agree with others that the supplied shim is “probably” meant for the stem, not the quill. The odd thing is the shim in the picture looks very long for a stem so this assumption may be wrong. For a shim to work with the quill it would have to be quite long similar to the picture. I’m not sure what to make of the picture.

The biggest problem I see with answering what you ask is that few if any have probably tried it before to see how it may or may not work. In theory it may work OK if you could find or make the right size shim but I doubt one is made because there would be so little demand for such an item.

Like threadless stem shims or seatpost shims I think it may work OK provided the shim was the right diameter and thickness (i.e. – it’s just friction between concentric tubes), but I strongly recommend you don’t try it on a tandem of all bikes. It’s not just about your safety but also that of your stoker.

I suggest you consider going to a quill adaptor and using a standard 1-1/8 threadless stem so you can install new bars of whatever size you prefer. If it’s an older tandem it’s probably a good time to replace the bars anyway.

[buck-50]

You could just go to nashbar and look for their $24 mountain comfort quill stem... It's pretty much got the same rise/angle as a periscopa but not as pretty. But, it comes in 1.125 quill. Profile makes a silver one too, apparently.

[henrypretz]

Thanks to everyone who took the time to share an opinion on this.

My current setup is a Sunlite 1 1/8" quill stem with a 25.4mm clamp.
The bars I'm using are Nitto Randonneurs with a 25.4mm clamp.
I was hoping to figure out a way to use the Nitto Periscopa stem 25.4mm clamp/22.2mm quill. Thought it might be fun to have a Nitto "cockpit" :)

The current stem works fine, so I'll just stick with it (will polish it out for a cleaner look)

Thanks again very much!
Henry

[Brian Smith]

Speaking as a longtime mechanic, I am familiar with the quill stem shim that you have mentioned. I would opine that if you wanted to curate an all-Nitto cockpit situation, the preferrable option would be a Nitto stem for 9/8 threadless quill mated to the Nitto quill adapter with 22.2mm stem. While I have occasionally used the shim that you have mentioned for single-person bike fitting purposes with on-hand stems, I would be wary of its use in a situation wherein the consequences (and liklihood) of loss of control when the stem rotates in relation to the steerer tube are increased via application on a tandem.
I wouldn't think that it's a case of Don't Ever, but rather a case of there being a better option, even within brand, and a tandem is not the place to be penny-wise and pound-foolish.

[henrypretz]

Speaking as a longtime mechanic, I am familiar with the quill stem shim that you have mentioned. I would opine that if you wanted to curate an all-Nitto cockpit situation, the preferrable option would be a Nitto stem for 9/8 threadless quill mated to the Nitto quill adapter with 22.2mm stem. While I have occasionally used the shim that you have mentioned for single-person bike fitting purposes with on-hand stems, I would be wary of its use in a situation wherein the consequences (and liklihood) of loss of control when the stem rotates in relation to the steerer tube are increased via application on a tandem.
I wouldn't think that it's a case of Don't Ever, but rather a case of there being a better option, even within brand, and a tandem is not the place to be penny-wise and pound-foolish.

Makes sense. Thanks Brian -