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'18 Transition Sentinel
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Discussion Starter · #1 · (Edited)
I'm still in a (long) process of choosing a new frame, with an intention of swapping my current fork ('03 TALAS) on it.

But I'm not sure how to determine what the longest headtube length of a new frame I can get away with my already-cut steertube, while (A) having all the headset/fork pieces safely engaged together and (B) still having a comfortable riding position.

My current rig has a headtube length of 110mm (4.33"), and I have five 5mm spacers (3 below the stem and 2 above) with it.

Can my 'max' headtube length simply be attained by taking out all 5 of the 5mm spacers (which gives me extra 25mm)? Is that still (A) safe and (B) comfortable?

I have narrowed down to 2 equally-apealing frames, so the headtube length might just become my determine factor...

* Frame #1 = 120mm (4.725") headtube (most likely OK, by taking out 2 spacers?)

* Frame #2 = 130mm (5.125") headtube (pretty close - maybe OK, by taking out 4 spacers!?)

NOTE: I've also head 160mm/6.25" for this frame #2. What a big difference! If that is indeed the case, I know this figure won't work for me, without asking. Anyway, I must confirm this further.

I just don't want to have a frame delivered, then be like, "Oh, nooooo!" :eek:

Thanks in advance,
- PiroChu
 
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Either should be fine

PiroChu said:
* Frame #1 = 120mm (4.725") headtube (most likely OK, by taking out 2 spacers?)

* Frame #2 = 130mm (5.125") headtube (maybe OK, by taking out 4 spacers!?)
Spacers are optional, just leave no more than 5mm stem above the end of the steerer tube. You may need a new stem with more rise if you have to get rid of the spacers under the stem.
 

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same headset?

you also need to keep in mind the stack height of the headset if you're using a different model than current setup, as well as the stem (steerer )height if using a different stem... But, if using the stem and headset, you seem good to go.

PiroChu said:
I'm still in a (long) process of choosing a new frame, with an intention of swapping my current fork ('03 TALAS) on it.

But I'm not sure how to determine what the longest headtube length of a new frame I can get away with my already-cut steertube, while (A) having all the headset/fork pieces safely engaged together and (B) still having a comfortable riding position.

My current rig has a headtube length of 110mm (4.33"), and I have five 5mm spacers (3 below the stem and 2 above) with it.

Can my 'max' headtube length simply be attained by taking out all 5 of the 5mm spacers (which gives me extra 25mm)? Is that still (A) safe and (B) comfortable?

I have narrowed down to 2 equally-apealing frames, so the headtube length might just become my determine factor...

* Frame #1 = 120mm (4.725") headtube (most likely OK, by taking out 2 spacers?)

* Frame #2 = 130mm (5.125") headtube (pretty close - maybe OK, by taking out 4 spacers!?)

NOTE: I've also head 160mm/6.25" for this frame #2. What a big difference! If that is indeed the case, I know this figure won't work for me, without asking. Anyway, I must confirm this further.

I just don't want to have a frame delivered, then be like, "Oh, nooooo!" :eek:

Thanks in advance,
- PiroChu
 

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'18 Transition Sentinel
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1,015 Posts
Discussion Starter · #4 ·
Yes, I'd like to just transfer the same headset (CK) and the same stem (& as many other parts I can transfer).

So, with the same headset & stem, going from a 110mm headtube frame to a 130mm headtube frame, I'd have to make up this extra 20mm simply by taking out four out of five 5mm spacers that I currently have, correct?

Also, do I understand correctly that the "front-wheel axle to handlebar/grip" distance will slightly change from my current setup, either by 10mm higher (if I put the single left-over 5mm spacer below the same stem) or by 5mm higher (if I put the single left-over 5mm spacer on top of the same stem), since the fork's steertube is kept to be the current length?

Thanks again,
- PiroChu
 

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yes, and yes, w/ a small caveat. That being the HT angle, if different than your current setup will change your axle to handlebar distance a tiny bit, perhaps making things a bit taller/shorter and closer/further out..
Have you downloaded one of the 'stem conversion' excel spreadsheet from previous threads here? lemme see if I can search it out... hmm, didn't find it.

I tink I got the program from naestep/speedhub nate quite a while back... email me here if you want a copy of it sergio underscore merino at usgs dot gov
For example:

Say your current head tube angle is 71 deg w/ a 110mm/7deg stem. This gives you a horizontal reach of 99mm and vertical rise of 48mm.
If your new bike has a 70 deg HT angle, then the horizontal reach changes to 98mm and rise to 50mm with the same stem. So, handlebar would effectively be 1mm shorter and 2mm higher.

Would this be discernable? I'd probably notice the change in steering characteristics more than that small of a change in where my handlebar was... could be compensated for by rotating your bars a bit, especially if riser bars.
In the end, you may get used to all the changes w/o any problems, or you may decide you need a different stem to get you back to a more comfortable spot...

Now, does Fox offer to replace a steerer tube for ~$50, like marzocchi does? ('zokie will do this once in a crown/steerers life)

PiroChu said:
Yes, I'd like to just transfer the same headset (CK) and the same stem (& as many other parts I can transfer).

So, with the same headset & stem, going from a 110mm headtube frame to a 130mm headtube frame, I'd have to make up this extra 20mm simply by taking out four out of five 5mm spacers that I currently have, correct?

Also, do I understand correctly that the "front-wheel axle to handlebar/grip" distance will slightly change from my current setup, either by 10mm higher (if I put the single left-over 5mm spacer below the same stem) or by 5mm higher (if I put the single left-over 5mm spacer on top of the same stem), since the fork's steertube is kept to be the current length?

Thanks again,
- PiroChu
 
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