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Discussion Starter · #1 ·
Just finished my second ride on a new-to-me Large 5 spot and have a couple of setup questions. After about 60mins into both rides the middle part of my back started to get sore . I took all the parts of my old frame and the bike I was coming off had a TT length of just over 23 inches while the Spot has a 24 inch TT. To partially compensate for this I slid the saddle forward about 1/2 inch leaving me a little more stretched out than before but not much. I thought being more stretched out took pressure off of your back but the opposite seems true for me. My stem is 100mm so maybe I need to get a shorter one? Any other setup suggestions? I am 6 feet tall if that helps.
 

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noosa2 said:
Just finished my second ride on a new-to-me Large 5 spot and have a couple of setup questions. After about 60mins into both rides the middle part of my back started to get sore . I took all the parts of my old frame and the bike I was coming off had a TT length of just over 23 inches while the Spot has a 24 inch TT. To partially compensate for this I slid the saddle forward about 1/2 inch leaving me a little more stretched out than before but not much. I thought being more stretched out took pressure off of your back but the opposite seems true for me. My stem is 100mm so maybe I need to get a shorter one? Any other setup suggestions? I am 6 feet tall if that helps.
I'm no expert on fit, but the 5 spot has a fairly steep seat tube angle. How does this compare with your previous frame? Additionally, you said you slid the saddle forward to compensate... you might be a lot further forward over the BB than you were previously.

Personally I'd try sliding the saddle back and getting a shorter stem, but that is how I like things set up. I run a 65mm stem on my long-top-tubed XC bike and really like it. I couldn't imagine running a 100mm stem on a MTB, even though that was considered a "short" xc stem a only a few years ago.

Experimentation sometimes leads to progression.
 

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I am 6' 2"

noosa2 said:
Just finished my second ride on a new-to-me Large 5 spot and have a couple of setup questions. After about 60mins into both rides the middle part of my back started to get sore . I took all the parts of my old frame and the bike I was coming off had a TT length of just over 23 inches while the Spot has a 24 inch TT. To partially compensate for this I slid the saddle forward about 1/2 inch leaving me a little more stretched out than before but not much. I thought being more stretched out took pressure off of your back but the opposite seems true for me. My stem is 100mm so maybe I need to get a shorter one? Any other setup suggestions? I am 6 feet tall if that helps.
I have a large spot and run a setback thomson seatpost and a hope 110mm stem. Before, I was riding a thomson 100mm stem and the front would lift on the climbs. Now that I lowered the stem and got a longer one, and it feels better. I moved the seat forward a bit and I can feel some power loss. I am still playing with my set up.........

I do not know if I have the shock set up right. I feel a bit of squat on the climbs. I think I have about 25 to 30% sag on the pushed rp3. I am probably 200lbs with gear and 80ml of water and tools on my back. I am running it at 190 psi - is that too low????????????
 

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noosa2 said:
I thought being more stretched out took pressure off of your back but the opposite seems true for me. My stem is 100mm so maybe I need to get a shorter one?
This would depend on some other factors like where the saddle height is in relationship to the bars and also how much of your weight is falling on your ass versus your hands. You said you swapped parts over but other than top tube length is everything else the same??? I think being more stretched out (if by this you mean flatter back angle, racer boy style) than I would think that this would acerbate back troubles. Usually a more upright position will alleviate back pain - assuming of course that you take the time to balance out your weight distribution (hands/ass)

Also where is your knee when the pedals are at the 3 and 9 o'clock position. Most people find it comfortable to have the forward knee directly over the pedal spindle. (KOPS) If this is out of whack and you are too far forward or back it can cause problems also. Lastly what do you want to accomplish with this bike? Do everything? More aggressive riding? If you answer that than others can help with ideas (shorter stem, etc)

Give us some more details and the Homers can help more...
 

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noosa2 said:
I thought being more stretched out took pressure off of your back but the opposite seems true for me. My stem is 100mm so maybe I need to get a shorter one? Any other setup suggestions? I am 6 feet tall if that helps.
It all depends on what's wrong with your back.

A more stretched-out position puts more strain on your back muscles (especially lower back) and pressure on your hands. A more upright position can be troublesome for riders with disc problems or any issue where compression of the back causes problems.
 

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Discussion Starter · #6 ·
CDtofer said:
Lastly what do you want to accomplish with this bike? Do everything? More aggressive riding? If you answer that than others can help with ideas (shorter stem, etc)

Give us some more details and the Homers can help more...
This is my "do everything" bike - really desert trail riding (2-3 foot drops)
 

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Discussion Starter · #7 ·
AW_ said:
I'm no expert on fit, but the 5 spot has a fairly steep seat tube angle. How does this compare with your previous frame? Additionally, you said you slid the saddle forward to compensate... you might be a lot further forward over the BB than you were previously.

Personally I'd try sliding the saddle back and getting a shorter stem, but that is how I like things set up. I run a 65mm stem on my long-top-tubed XC bike and really like it. I couldn't imagine running a 100mm stem on a MTB, even though that was considered a "short" xc stem a only a few years ago.

Experimentation sometimes leads to progression.
I think you might be right - longer top tube but steeper seat tube angle means that I probably a lot further forward than I think I am. I'll give the saddle back and shorter stem a try.
 

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Discussion Starter · #8 ·
Blue Shorts said:
It all depends on what's wrong with your back.

A more stretched-out position puts more strain on your back muscles (especially lower back) and pressure on your hands. A more upright position can be troublesome for riders with disc problems or any issue where compression of the back causes problems.
Sore muscles - spinal erectors I think (been a long time since I took anatomy and pys)
 

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I'm 6' and use a 75mm Azonic shorty dh stem with three wide spacers with easton monkey lite risers on my Spot. I tried my longer stems and didn't like them.

I like to use the saddle adjustments for the knee to pedals fit, and weight distribution adjustment.
 

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What was your prior ride? It may be that you have some differences in bar and stem position besides just the longer TT, due to differing headtube length and angle - even though you swapped the same bar and stem.

My Burner is rigged for more stretched out XC riding with a 120mm Thomson stem with a 5 degree rise and a RaceFace Low rise XC 1 inch rise carbon bar- on the Spot I opted for a 100mm FSA stem with a 6 degree rise and an Azonic Double wall 1.5" rise. The Spot is noticeably more upright and comfortable on the lower back, though it's not as "racey" feeling. This different feel is on two frames that are virtually the same geometry-wise except that the Spot has a 1 degree slacker headtube angle.

Depending on your prior bike's headtube length and headtube geometry you may be getting more stretched out than you realize just based on top tube length comparisons.
 

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In general, sliding your seat too far fwd will definitely make for a sore back. Since the Spot already has a pretty steep seat tube at 73 degrees, you are now probably significantly forward from where your old bike had you. I would put the seat back where it was, and go shorter stem.

IF your old bike fit you well, here is a good way to start out with a new build. Find something perfectly vertical (I use the molding on the corner of my garage door), and put the center of your crank on it, then see how far behind that vertical line your seat tip is. Duplicate that to start the fit setup on your new bike. That measurement, along with seat height is the central starting point for any fit.

Next, go from there to duplicating the other dimensions of your old, perfect fitting bike like seat tip to bar center, floor to bar center, etc.
 

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I'm 6' also with a 100mm stem and have the seat pushed all the way back on the rails. Although with a Thomson straight post, it's not back that far since the large clamp doesn't allow much adjustment. This is the best setup I've tried. Works for me anyway. Good luck.
 

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Discussion Starter · #13 ·
Homebrew said:
I'm 6' also with a 100mm stem and have the seat pushed all the way back on the rails. Although with a Thomson straight post, it's not back that far since the large clamp doesn't allow much adjustment. This is the best setup I've tried. Works for me anyway. Good luck.
I pushed the seat all the way back on the rails (like I had on my old frame) and put on an old 90mm stem that I had so I'll see how that goes this W/E.
 

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Noosa2,

I'm 6' with about a 33" inseam. I ride a large spot. The seat angle as mentioned earlier is probably the issue. I never felt right on mine until I replaced the 120mm stem with a 90mm and bought a setback post (1.5" of setback). It looks like you're on the right track. I'd recommend the FSA SL220 seatpost so you can have some adjustment room with the rails instead of "all the way back".

Best of luck
 

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A lot of people - myself included - have found a little more rise in the stem than what you're used to is a good thing. I went from a 5 deg to a 10 deg and now run a 15 deg stem with low rise bars. The Spot - for me - just seems to *feel* better witth a slightly more upright position.
 

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Discussion Starter · #16 ·
noosa2 said:
I pushed the seat all the way back on the rails (like I had on my old frame) and put on an old 90mm stem that I had so I'll see how that goes this W/E.
That seems to have done the trick - 75 min ride (way too hot to ride any longer then that) without back pain.:thumbsup: Still... think I would like a bars to be a touch higher so I am better able to get the front up. I have one small spacer (1/8 inch?) still on top of the stem so I'll drop that below the stem for my next ride and see how that works.
 

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Discussion Starter · #17 · (Edited)
k1creeker said:
Noosa2,

I'm 6' with about a 33" inseam. I ride a large spot. I'd recommend the FSA SL220 seatpost so you can have some adjustment room with the rails instead of "all the way back".

Best of luck
My current post has some set back but it would be nice not to have the saddle all the way back on the rails. I'll check out the FSA post you mentioned.
 

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Straight Spot

While we are on the subject of fitting, I have a question. I notice that my Spot handles perfectly in most situations, however, when bombing down a fire road and entering a sweeping turn I noticed the bike really wanted to keep going straight (more so than my previous bike) even when I leaned it over. Any suggestions? I run a Z1 which I believe has a fairly long a2c, could that be the problem?

thanks
 

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evilmoose While we are on the subject of fitting, I have a question. I notice that my Spot handles perfectly in most situations, however, when bombing down a fire road and entering a sweeping turn I noticed the bike really wanted to keep going straight (more so than my previous bike) even when I leaned it over. Any suggestions? I run a Z1 which I believe has a fairly long a2c, could that be the problem?

thanks
I won't say its the problem but longer A2C will slow down the steering I have an AM1 on my Spot and find this sometimes, course I change my tires like the preverbial so this dosen't help and they can change the steering characteristics allot 2.

I'm going to try a PIKE 454 which has a lower A2C, which I did demo on an Epiphany, which was good as I could switch back and forth to compare.

Pike seemed stiff but not as supple as my AM though Im sure this was setup, T need yr help.

Will post elswhere for this..
 

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Handling

Thanks,

I'm going to a Pike U-Turn, tscheezy has recommended one (pretty emphatically). Just a matter of saving up some $$$.

I think the a2c length of the Z1 definitely slows things down at times. I lowered my handlebars (switched some spacers from below to above stem) and that seems to have helped - maybe put a little more weight on the front wheel.

I'll keep you posted:thumbsup:
 
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