I just installed Sinz cranks on my road bike. It works fine except I didn’t like the Q factor. I used a 107mm bottom bracket. Anyone try a 103mm spindle? I measured the chainrings being 5mm further out in relation to the bottom bracket shell than 105 Hollowtech 2 cranks. Thanks
Paul
Wait, sinz like the BMX cranks?
huh.
If you’re into really small cranks, I have a 115’s that came off my 4yr olds BMX bike. Why would you run sinz cranks, deal to good to pass up? Confused as well.
Yes, he (or she) mean the BMX cranks, if you want to go smaller than 165, they are one of a few choices. I have 135mm with 34/50 on my 9 y/o son’s bike.
I thought bb width was determined by the bb shell and not the bb, I could be wrong though.
Spindle length is determined by the crank. Shell width of BB is determined by the frame. Most older road frames have a 68mm shell width. I am just trying to get my chain line closer to the bottom bracket shell. I just wondered if anyone tried a 103mm spindle length with the Sinz square taper cranks. I found that 160mm cranks seems to be my sweet spot.
I use the 103 width very regularly with the Origin 8 cranks which I believe are the same deminsions as the Sinz cranks. 103 is a standard Shimano part and the width seems to line up better with the front deraileur.
I have the Sinz cranks on my trainer bike. Would not hesitate for a second to put on my tri bike with a taper square BB. My tri bike actually has a taper square BB with an SRM. Taper square is not that much heavier and really easy to use.
Thanks John, I am going to give it a shot. I more than enough room for the chainring to clear the chainstay, but was concerned with that short of a spindle that the outside of the crankarm that is on the spindle would be rubbing on the inside of the bottom bracket installation teeth that you find on Shimano BB’s and the like. I went with Sinz because I could get them through my LBS (through Quality). Do you know if the Origin 8’s are badged as an another brand through different suppliers? Thanks again! Paul
Origin 8 is the house brand for J&B Imports. They are a major distributor like Quality, almost every shop orders from J&B. They have c/rings from 30 - 53 that work with the cranks.
John, is it normal to go the other way on a smaller frame? I’m on a Felt B2 48cm (650c). My chain line was off with Origin8 cranks (155mm) and a 107mm bb, so we bumped up to a 113 bb.
I don’t know about that but I can’t think as to why going wider would be needed because of a 650 frame. If your chain line is correct now and it shifts good then that is some good information for others to be aware of, thanks.
John, did you try out any of the other BMX cranks? Such as Answer or AC mini-cranks? Or the Crupi Expert integrated crank? Just wondering if these would work with a double chain ring, and BMX dealers seem baffled or annoyed at the question.
I have not tried any of those others, I had just stumbled into the origin 8’s and they worked so I have not looked further. Rotor has just come out with some very nice cranks down to 145 so that will probably be the best option as they are available.
Yes, I’ve talked to the Rotor folks, I’m sure it’s a great product but the cranks are pricey–it’s the 3d+ model at $660, plus another $90 for the adapter.
Hey John thanks for the info about J&B importers and also would like thank you for your input for the spindle length. 103mm spindle was as close as one could get. I have maybe 1-2mm of space between the crank and the bottom bracket shell. Chain line is better and shifts well. I used an IRD bottom bracket which is fairly smooth. Not as smooth as say a UN72 but certainly acceptable. Thanks again
John,
How would you review those Origin 8 bottom brackets? On par with Shimano UN series? I have seen some real junk bottom brackets (JIS type) from off brands over the years so would like to hear from someone who has seen them in use. Thanks!
I’d say that there is no chance that a $12.00 B/B is on the same level as a $35.00 B/B so the UN series should last longer. It’s kind of the same with the crank arms but if you want to see how these shorter cranks work with out throwing down $600.00 for real good ones then this is not a bad gamble. For a age grouper that does 100 - 150 a week these should do well for a couple of seasons, for longer distance racers then you might want to spend more.
Hey john…Not sure you’re still following this thread but I was wondering what length most of your customers are using? I just went from a way oversized, stock 175 to 165 and feel much better but wondering how 155 might feel???
I have Sinz 145mm cranks on 3 of my bikes now, on 2 of them I have the square taper BB I use a Token 102mm BB. the other one I use a 107mm FSA It is a bit wider but I really don’t notice after a short while riding, I find that I can really spin with these short cranks. I have Sram Force 22 with FSA 50-34 chain rings and Campy 11 speed 14-27 on this bike, on my TT bike I still use 50-34 with 12-27 Campy 10speed cassette and Campy derailleurs.