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Discussion Starter · #1 ·
Hi,

I am trying to properly set the front of my 5-spot. I have just switched from an XC racer with flat bars and am trying to understand how my 45mm riser bar needs to be set, and as a result which stem length I need.

Can anyone please help shed some light on riser bars?
1.What is an "upsweep"?
2. Ideally, should I set my grips to be horizontal to the ground, or angled up significantly?

Thanks!
Tal
;)
 

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It sounds like you may be trying to replicate the reach of your XC bike on your Spot. A word of advice if this is the case- don't do it. I think a good starting point for stem length on a Spot would be 90mm for a small, 100 for a medium, 110 for a large, and 120 for an XL. Invididual preference and fit will help you figure out what works best, but most riders seem to fall within +/- 10mm (20mm tops) of what I've listed.

Riser bars usually have two planes of sweep measured in degrees- one for upsweep, one for backsweep. Many bars list both measurements but some do not (I've never figured out if that's because they have sweep in only one direction or not though). Upsweep is the angle at which the bars continue to angle upwards in the same plane with the actual rise. Backsweep is the angle at which the bars angle back towards the rider.

Assuming your bars have both you'll probably want to have the rise in the bars perpindicular to the ground (i.e. vertical), so that the upsweep is actually going up and the backsweep is going back. Some people rotate the bars back from vertical, but then your rise (and upsweep) will just be angled back at you, meaning you could accomplish the same thing by running a shorter stem and lower rise bar. At that point your backsweep would actually be angled down too.

If this doesn't make sense or sounds too complicated just set it up how you think best and experiment a little to find what you like. Like I said, it all comes down to individual preference anyway.
 

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If you are using a 45 mm rise bar, you may want to notch the stem size down a bit, ie. 100mm for a large spot...etc.....Riser bars usually have the ends of the bar come back towards the rider more [7-13 degrees back] than flat xc bars [3-5 deg. back] - it puts your wrists at a more natural angle. Flat XC bars have very little backsweep, so it forces the rider to bend the elbows in order to keep the wrist angle comfortable, riser bars help to alleviate this extreme positioning. I like a bar that really sweeps backwards a lot , like a salsa moto ace dh riser [13 degree backsweep] - very comfy.

As for getting the right position, just loosen your stem bolts enough so you can still rotate the bar in the clamp....just sit on your bike, close your eyes and let your hands move into the position that feels right, let go [the bar wont move since the clamp isn't that loose] and tighten er up....
 

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I have an Excel program that will help you to choose the right stem and bars...and spacers, if you want.

You just type in your current setup and it will show you the horizontal and vertical hand position change as you change stem lengths and angles...bars and spacers. Send me a pm with your email address if you want it.
 

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Discussion Starter · #5 ·
Well, here is my specific problem:

I am 5' 11.7", with a 33-34inch inseam, and I am coming off a large Specialized SWorks FSR XC-race bike, which had a 2.36" top-tube and a ~120mm 10 degree stem, first with a flat bar and then with a 1"riser. With these setting, I felt very comfortable.

I have just switched to a large 5 spot which has a 2.39 inch top tube, with a 90mm 17 degree stem and a 45mm riser handlebar, and strangely am also very comfortable. I tried a 105mm 10 degree stem on the 5 spot, but I felt REALLY stretched.

Basically, I am trying to understand why such a short stem feels comfortable on the spot. Originally, this also made me question whether I should have taken a medium 5spot instead of the large, BUT the large's top-tube is MUCH closer to my previous bike than the medium (which has only a 23 inch TT), and I see a lot of people are using a 90mm stem on their 5spots (at least in this forum).

Here is my math so far:
1. The top tube is ~8 mm longer on the spot.
2. As you well point out, the 45mm riser now requires a significantly lower stem placement than I had before, which moves the handlebar forward another ~8mm as compared to a 1" riser stem. - hence the need for a shorter stem when using a 45mm riser.

--> Thus, I can account to around 15mm of stem length difference between my 5spot and previous Specialized.
Still, I do not understand where another 10mm went...
- Maybe its because the bar is now higher up (same height for handlebar and saddle) as compared to my Specialized, where the bar was 1 inch below the saddle?
- Maybe its because of the significantly wider bars on the 5spot (26" as compared to ~23").

Any ideas?!?

Thanks,
Tal
 

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tald said:
Well, here is my specific problem:

I am 5' 11.7", with a 33-34inch inseam, and I am coming off a large Specialized SWorks FSR XC-race bike, which had a 2.36" top-tube and a ~120mm 10 degree stem, first with a flat bar and then with a 1"riser. With these setting, I felt very comfortable.

I have just switched to a large 5 spot which has a 2.39 inch top tube, with a 90mm 17 degree stem and a 45mm riser handlebar, and strangely am also very comfortable. I tried a 105mm 10 degree stem on the 5 spot, but I felt REALLY stretched.

Basically, I am trying to understand why such a short stem feels comfortable on the spot. Originally, this also made me question whether I should have taken a medium 5spot instead of the large, BUT the large's top-tube is MUCH closer to my previous bike than the medium (which has only a 23 inch TT), and I see a lot of people are using a 90mm stem on their 5spots (at least in this forum).

Here is my math so far:
1. The top tube is ~8 mm longer on the spot.
2. As you well point out, the 45mm riser now requires a significantly lower stem placement than I had before, which moves the handlebar forward another ~8mm as compared to a 1" riser stem. - hence the need for a shorter stem when using a 45mm riser.

--> Thus, I can account to around 15mm of stem length difference between my 5spot and previous Specialized.
Still, I do not understand where another 10mm went...
- Maybe its because the bar is now higher up (same height for handlebar and saddle) as compared to my Specialized, where the bar was 1 inch below the saddle?
- Maybe its because of the significantly wider bars on the 5spot (26" as compared to ~23").

Any ideas?!?

Thanks,
Tal
I just sent you the program. You have to consider that the Spot has a very short head tube. The seat angles also play into the calculations.
 

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Secret Set Up Rule

Here's a secret: If you want, it is ok to set up your new Spot with a little xc slant. You bought it, any setup that feels comfortable is fine.

Initially, you may just feel better with a setup that is somewhat similar to what you had on the ole FSR XC. Slowly, you may find the Spot just seems happier with the bars a little higher and further back than that.

Who knows why? Who cares? It just seems to work.

As far as your question of whether you should have gone with a medium frame instead of the large, I don't think so. When stuck between sizes, I think the better ride is gained by choosing the larger frame paired up with a shorter stem. Unless all your riding is on such tight trails that a slightly shorter wheelbase really matters.

Plus, a medium underneath somebody as tall as you would require so much seatpost extension that it would be stylistically embarassing!
 
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