Hello,
During a recent bike fit, it was recommended to me that I should be using a 155mm crank instead of my current 165mm crank.
I’m wondering if anyone has switched out their former crank for a different sized crank and how beneficial of an upgrade it was?
Also, are their any specific 155mm cranks for a tri bike that anyone would recommend? Thank you.
Go with Rotor.
Go with Rotor.
Thanks. Any specific model? Ideally, I’m looking to spend under $300.
I run a Rotor 155 mm crank on my tri bike. I have used it since about 2015 but I did take a hiatus from triathlon for several years.
I like it a lot. I rid a more standard 170 crank on my road/gravel bike and it takes me one to two rides to adjust to the difference.
I went with the shorter crank arm due to lack of flexibility. It allowed me to get lower in front.
Go with Rotor.
Thanks. Any specific model? Ideally, I’m looking to spend under $300.
The Vegast is in your price range but 165mm is the shortest
The Aldhu goes to 155mm and is more$
I ride COBB 155. The benefit for me was opening my hip angle. I have hip impingement that is a cam and a pincer so it helps alleviate that. There might be aero dynamic benefits but I think it requires testing.
Not 155mm but I went with a Shimano 105 160mm crankset…cheapest solution that I could find.
Not 155mm but I went with a Shimano 105 160mm crankset…cheapest solution that I could find.
I have that crankset on my tri bike and am very happy with it.
(R7000 Shimano 105 160mm)
I bought a set of the BBK 155’s off of ebay (from australia) added rotor rings and couldn’t be happier!
I ride COBB 155. The benefit for me was opening my hip angle. I have hip impingement that is a cam and a pincer so it helps alleviate that. There might be aero dynamic benefits but I think it requires testing.
Thank you - that speaks to me because I also have a hip impingement in one or both of my hips due to running during the fall time. Truthfully, I never gave any thought into the length of my crank until I got a bike fitting a couple of months ago. I bought my bike used and it came with a 165mm length crank. At 5’5", during my bike fit, one of the recommendations was to switch to a shorter 155mm crankset. I’ve just been debating whether or not the upgrade would be beneficial.
Essentially, like all of us, I am looking to optimize my performance on the bike as much as possible and make it an equally comfortable and efficient experience for me throughout the bike and prior to the run.
My wife is 5’4" and she runs 150mm. 165-155 isn’t much of a change to be honest, you aren’t going to feel it. If you went to 150mm you probably wouldn’t feel it either.
I just went through this process for the same reasons. I’m 6’0", and my fitter took me from stock 170mm cranks to 165mm Rotor ALDHU’s. It allowed him to raise the saddle and lower and lengthen my front end. It ended up being more aero and comfortable at the same time, and my legs absolutely feel better off the bike. The 5mm change was noticeable during the fitting, and I started noticing the benefits in the weeks after. I’m happy I made the change and I’m swapping cranks on my road bike as well.
Thank you - will going from 165 to 155 change the fit of the bike? I have a follow-up appointment for my initial fitting in about a month, so I’m wondering if I should just get the 155mm prior to then so he can make any additional adjustments as needed.
In my case, yes, and it was only a 5mm difference in crank length. My fitter recommended the cranks during my offseason fit session. After we swapped them out I went back for another re-fit (this was covered under payment for the first fit), where we raised the saddle a bit more and adjusted the front end.
Yes, if you can do it before.
Here is the basic concept.
Shorten cranks by 10mm then the bottom of your pedal stroke is 10mm higher so the saddle goes up 10mm. Does that make sense? The saddle then can go forward a tad if you want not a lot. When you raise the seat it moves it farther back since it is at an angle. Your front end can be adjusted too. Your fitter will help with all of this.If you are doing it all on your own You can do the first two things very easily, but keep track of the the movements. I put a piece of black electrical tape on the seat tube so I know the starting point and then can measure easily. I aslo mark with marker or tape for the rails so I know the starting point.
The front end can then be adjusted as your comfort allows or fitter recommendation.
Thank you - will going from 165 to 155 change the fit of the bike? I have a follow-up appointment for my initial fitting in about a month, so I’m wondering if I should just get the 155mm prior to then so he can make any additional adjustments as needed.
Your fitter should have a fit bike with adjustable crank length.
I’ve done this… If you like going uphill really slow then 155s are good….
I don’t miss those short levers… maybe get a new bike fitter as they are not all created equal.
I’ve done this… If you like going uphill really slow then 155s are good….
I don’t miss those short levers… maybe get a new bike fitter as they are not all created equal.
At 5’5â€, why would 155 hinder my performance? My understanding is the guy I saw is one of the best around.
165-155 isn’t much of a change to be honest, you aren’t going to feel it. If you went to 150mm you probably wouldn’t feel it either.
If your current position has you right at your limits as far as joint angles go, then any difference becomes noticeable. Going from 170 to 165 was a big improvement for me. With 170, I was having a bit of discomfort getting over the top of the pedal stroke, with 165 that’s all gone. So just 5mm made the difference from tolerable to comfortable…
Not 155mm but I went with a Shimano 105 160mm crankset…cheapest solution that I could find.
And if you put ultegra Rings on it, it is still pretty light
.