Considering shorter cranks advice wanted.

[DuncanWatson]

I am considering shorter cranks. I currently am running a 170mm Ultegra crankset 50/34. I am wondering what is a good option to go to 165 or 160mm crankset. I would like to be able to get q-rings to go with it. I am wondering what choices have been made before by the trailblazers? I may consider going with a rotor crankset but the cost seems pretty high.

Thanks in advance.
djw

 

[ratz]

Here are a couple starter items to consider

1) 165mm is the shortest you will find in stock configuration that are compatible with the bike
2) Sub 165mm requires custom modified cranks in most cases aka bikesmithdesign.com or similar.
3) Sub 165mm will have an integrated spider and in all cases I've explored and will limit you to pedal-based or wheel-based power meters
4) Mounting Rotor Cranks on a Yellow vendetta can be done but check with me for the how too before you invest if you go that route.

QRings will work with anything in general but the shorter your cranks the less value they provide from the little Ring; to the point that if you are running a 34T your little ring might as well be round if you are at 155mm or less.

What you really want to do is arrange to rent/borrow larry's adjustable custom cranks and see if you prefer shorter.

 

[DuncanWatson]

I normally use 165mm cranks. I was looking at these cranks Rotor 3D24 Road Compact Crank in 165mm. They are available as low as 155mm but not in stock. Would this require a lot of custom work?

 

[trplay]

My advice is to ride what you have and establish a baseline. Then one change at time and you will know if it's the Cranks-rings- seat or maybe just voo-doo.

 

[DuncanWatson]

You aren't wrong, it is just I was feeling twinges in my knees the day after and that is a warning sign for the cranks. It may have been from the cleat that lost a screw and got out of position but ...

 

[Rick Youngblood]

You aren't wrong, it is just I was feeling twinges in my knees the day after and that is a warning sign for the cranks. It may have been from the cleat that lost a screw and got out of position but ..

Speed Larry is Running 150mm and has an inseam/exseam similar to you Duncan. I'm running 155mm and have been now for quite some time. I'm 5-9 with a little longer xseam than yours. My knees have been good for some time now, for me this is an area I don't like to mess with - my personal feelings only - my knees seem to be temperamental to slight changes, like q-factor, boom length, etc.

If you can't get a hold of Larry's adjustable's to test out. You may want to go with the bikesmith as Bob suggested and go with this "Compact Double 34/50t Chainrings 137.5mm to 158mm
Rings are the same as 2013 SRAM top of the line "Red" 10 speed" - Q-rings will work with these (this is my current setup). Then you could always upgrade to the pricier Roto 3-D's, and sale the Sram's here .

 

[ratz]

I normally use 165mm cranks. I was looking at these cranks Rotor 3D24 Road Compact Crank in 165mm. They are available as low as 155mm but not in stock. Would this require a lot of custom work?

As far as I know those aren't made any more below 165mm. Hence out of stock. Below 165mm now only available in 3d+ which are bb30 and the future. But BB30 won't work, I got it really really close. @Robert Holler and I would have been smiling ear to ear if I had been able to make it work. So we run the 165mm here. In the end both the 3D and 3D+ are just a tad tricky to get mounted if you haven't used the UBB before. The main problem is then can cause your BB clamps to be a little too far to the left by 1.5mm which messes with the FD chain line. Once you know that if you pair them with an angular bearing BB then the preload install just about perfect.

Now after all of that if you can find a used Rotor 3D24 in the short sizes you'd be good to, spend less, and all you'd need is a fresh BB.

I will say this; on my CT700 I preferred 155mm and we did test shorter here and I had ordered 155mm 3D+; it sure feels to me (can't verify or prove) that if I like 155mm on recumbent A, I also like that on the Silvio/Vendetta. Perhaps a future CB design will support BB30; that would open up huge options for all of us.

 

[Rick Youngblood]

future CB design will support BB30

+1 on that!

 

[DuncanWatson]

I got a deal ($20) on some 165mm ultegra 130 bcd cranks. I will order a set of q-rings in 130bcd to match. I normally use 165s and q-rings on all of my bikes so this is just my normal. I don't normally use 130 bcd but there is only one lost gear going from 34 small to a 39 small. I can live with a low gear of 32". Though I did find that to start on any hill I need to be way downshifted. I did some practice yesterday evening focusing on stop/starts. I do best in a much lower gear than the one I would continue in on the same slope.

 

[DuncanWatson]

So I am thinking of going 53/39 Q rings + ultegra 165mm cranks in 130 bcd. That should work?

 

[Jeremy S]

So I am thinking of going 53/39 Q rings + ultegra 165mm cranks in 130 bcd. That should work?

Are they the newer four bolt style cranks? I believe with those you have to order compatible Q rings, and the adjustment options are very limited and might not work out on a recumbent.

 

[DuncanWatson]

5-bolt spider

 

[DuncanWatson]

I pulled the trigger. I got a reasonable deal on a 53/39 set of q-rings and a great deal on an ultregra 165mm crankset sans rings. Everything arrives next week.

 

[Alan W Dolbeer]

My four year old Silvio 1.5 came with Ultegra triple (round) ring 155mm crankset and it has worked well for me. I ordered the V20 earlier this year with the Driveline Zele 50/34 Compact 165mm crankset (also round rings). I must say I prefer the 165mm length crankset arms on the V20 to the 155mm arms on the Silvio.
I have seven bikes of various frame styles and am happy with round rings. Never tried Q-rings as I don't want to deal with switching between round and oval ring bikes. I guess crankset length and ring shape is a very individual choice. I am 5'8" tall with an x-seam of 41".

 

[castlerobber]

I used 165mm cranks on both my tadpole trikes, as well as on my Silvio 1.5. Seems to work pretty well for me with an x-seam of 40.5". I was glad to see that the QX100 comes with 160mm cranks.