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stem length
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I know this topic has been talked about several times before So I apologize Upfront for the redundancy. During my fit this past weekend With the guru system it came back with A lot of bike options in a lot of different brands. However The one thing they all had in common Was it was a full size bigger than I expected And had rather long stems ranging from 120 to 140. So I guess the question is Is there a different solution And or is it okay to run stems of this length on Tri bikes.
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Re: stem length [Fishbum] [ In reply to ]
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Did they give you your pad X,Y coordinates?

If so what are they?
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Re: stem length [jaretj] [ In reply to ]
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I don't see that on my report Is that the same as my pad Stack and pad reach
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Re: stem length [Fishbum] [ In reply to ]
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Pad reach 541
Pad stack 651
Hx 556
Hy 596
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Re: stem length [Fishbum] [ In reply to ]
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Are you 6'4" Because that is a really long stem on a Tri bike? Normal sized humans tend to have a stem length of 90-100mm and you darn near have to special order a 140 stem from Belgium. It is not something most shops stock because there aren't even many people on 120 or 130mm stems.

My question would be whether the fit seemed more comfortable and whether it was an improvement. Before/after pictures would be helpful.
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Re: stem length [Fishbum] [ In reply to ]
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I run a 120mm stem on my tri bike (also have 120mm on my roadie...just coincidence). No handling issues (I'm 5'8" for ref.). In both cases I went with a smaller frame to get a lower stack, and needed a longer stem to get back the reach.

For the aero position, it's where the pads end up that matters, regardless of stem length.

The basebar position should be roughly equivalent to a hoods position on a road bike, and 120mm is what I would consider on the high end of "normal" (100mm is the "classic" stem length and I'd consider 80-120mm to be in the normal range).

If you need a super short or long stem, it raises the issue of the frame size being optimal.

ECMGN Therapy Silicon Valley:
Depression, Neurocognitive problems, Dementias (Testing and Evaluation), Trauma and PTSD, Traumatic Brain Injury (TBI)
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Re: stem length [grumpier.mike] [ In reply to ]
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Here's a pic. It was to find a new bike. That was Guru recommendation. Im 5'11. System reccomending 58 with 120 to 130 stems. Some even 140... Fit was good but i dont understand the systems choices.
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Re: stem length [Fishbum] [ In reply to ]
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Based on that static pic and my semi-informed opinion, I think your arms are not resting on the pads, i.e. pads are way forward of where they belong.
Also, saddle height appears high bc your leg is straight.
Together, the bike becomes too tall and long, and recommended bike a size too big.
Pull the pads back 4-5cm and drop the seat 2-4 cm and you're closer to a proper eyeball fit. And a size 56 (nominally) w/ a 100-120mm stem.
IMHO.
-J

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Life is tough. But it's tougher when you're stupid. -John Wayne
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Re: stem length [Fishbum] [ In reply to ]
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Odd looking fit. It looks like an effective seat tube angle of 90 degrees because your hip socket sits directly over the bottom bracket and the straight leg indicates seat height is too high. Arm pads look a little too far forward as well.

I would NOT buy a bike based on that fit until you are sure it would be comfortable.
Last edited by: grumpier.mike: Oct 24, 16 19:43
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Re: stem length [Fishbum] [ In reply to ]
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I'd echo what others are saying. Sounds like the person using the system is not trained in it enough either, because they should see that it's not right and the 140 mm stem should raise alarms for them. If you go with a 130 or 140 mm stem, you risk putting your weight way too far forward, which will make handling awkward and could even be dangerous if the weight of your arms is pushing down in front of the front axle (this shifts too much weight off the rear wheel and onto the front wheel – not good).

If you paid for the fit, you should get money back in my opinion.
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Re: stem length [Fishbum] [ In reply to ]
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Fishbum wrote:
Here's a pic. It was to find a new bike. That was Guru recommendation. Im 5'11. System reccomending 58 with 120 to 130 stems. Some even 140... Fit was good but i dont understand the systems choices.

The stem recommendations probably assume the pads are directly over the basebar. Far better to fit the basebar position, then place the pads/extensions (assuming the cockpit you are using has enough fore/aft flexibility).

Since you seem to want the pads 1/3 of the way up your forearm (vs. your elbow right at the back of the pad), the pad reach numbers are going to be long. I'd size the frame based on what the reach would be assuming the pads were back by your elbows (subtract 4-5cm by the looks of it).

ECMGN Therapy Silicon Valley:
Depression, Neurocognitive problems, Dementias (Testing and Evaluation), Trauma and PTSD, Traumatic Brain Injury (TBI)
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Re: stem length [Titanflexr] [ In reply to ]
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Thanks for the feedback I think I'm going to reach out to the fitter And see about going back in and doing some tweaking. I think part of the problem Maybe He was getting some Bad feedback from me Because of how long I've currently been riding in a bad position
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Re: stem length [Fishbum] [ In reply to ]
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For the most part I agree with the other comments up to this point. I would push for keeping the stem a little shorter when you're putting that much more weight on the cockpit and front wheel.

My n=1 is being 6' with 6'4" arms and a Retul fit putting me on well known tri bike with the stem length at 130mm. For about 1.5 years and 3-4 falls, I just thought that's how a tri bike was supposed to feel; twitchy and tons of weight on the front wheel. In a race the steerer tube cracked between the headset cap and first of two spacers. Very scary. Turns out there was also a frame defect, but that's unrelated.

The retailer and manufacturer were great in helping me nab a replacement frame and said yes when I asked if I could go up a size. The fitter thought I was dumb, but I didn't care. The next size was almost exactly 20mm longer and 20 mm higher. I lost the two spacers, dropped the stem down to 110 and never looked back. I was finally riding 'in' the bike than on the front wheel. It's been 2+ years since making the switch. I know the stem length doesn't dictate exactly where your pads, center of gravity, etc. go, but it's a big part of the equation. Personally, I would steer clear of any recommendation putting that long of a stem on a tri bike. Road bike though, no problem. I usually ride a 120-130 stem with a handlebar reach somewhere around 80mm. The weight is so much further back that it's just fine.
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Re: stem length [Fishbum] [ In reply to ]
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Fishbum wrote:
Thanks for the feedback I think I'm going to reach out to the fitter And see about going back in and doing some tweaking. I think part of the problem Maybe He was getting some Bad feedback from me Because of how long I've currently been riding in a bad position

Fwiw I think the position looks ok (assuming that's a pic where you weren't pedaling, making it hard to judge the seat height). If you were pedaling the seat is too high.

Do you have a vid?

ECMGN Therapy Silicon Valley:
Depression, Neurocognitive problems, Dementias (Testing and Evaluation), Trauma and PTSD, Traumatic Brain Injury (TBI)
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Re: stem length [Titanflexr] [ In reply to ]
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Spoke with the fitter And he agreed about my elbow placement. We're going to take another look at things tonight hopefully. The picture I posted with static and I was not pedaling I do have a video but it's extremely grainy As I took it with a cell phone that had sweat on it. Still struggling with the thought That I would be A 58 and a Cervelo And a 60 and a Cannondale slice As I am only 5:11
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Re: stem length [Fishbum] [ In reply to ]
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Those are way too big.

Your fitter has no idea what he is doing.
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Re: stem length [Fishbum] [ In reply to ]
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was this fit done at world cup ski and cycle by chance?
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Re: stem length [tcaldwell369] [ In reply to ]
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Yes?
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Re: stem length [grumpier.mike] [ In reply to ]
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grumpier.mike wrote:
Normal sized humans tend to have a stem length of 90-100mm and you darn near have to special order a 140 stem from Belgium. It is not something most shops stock because there aren't even many people on 120 or 130mm stems.


I disagree - I have been using 130mm and 140mm stems for years and they feel no different from a 90 or 100mm stem. If you measure the difference between a 100mm stem and a 140mm stem it is obviously 40mm which ain't very long.

As for availability, I have never had any problem acquiring the longer stems online.
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