Doug Burton
Zen MBB Master
... or upgrade for Sofrider V1/Freerider...
http://www.chucksbikes.com/store/cr044.htm
http://www.chucksbikes.com/store/cr044.htm
Darn Nice conversion crankset
- Thread starter Mark B
- Start date
Doug Burton
Zen MBB Master
Hi Mark,
It's a 155mm crank length crankset. 52/39 would make the gain ratios really high. the 50t/36t matches the 155mm crank really nicely, giving adequate low and a "keep the legs moving " high for speedy downhills.
best,
It's a 155mm crank length crankset. 52/39 would make the gain ratios really high. the 50t/36t matches the 155mm crank really nicely, giving adequate low and a "keep the legs moving " high for speedy downhills.
best,
MailSeanBell
Active Member
Would this mount on a Freerider V2 easily? And if so would it:
A) Add more gears higher and lowers? I find when I'm pulling a trailer I need a few more gears.
B) Require a new crank arm on the other side?
C) What sort of derailer would I need to buy to make that work? Also... Could I mount that without a derailer and just manually shift it over when I'm pulling the trailer? (Probably not ideal but just a thought...
A) Add more gears higher and lowers? I find when I'm pulling a trailer I need a few more gears.
B) Require a new crank arm on the other side?
C) What sort of derailer would I need to buy to make that work? Also... Could I mount that without a derailer and just manually shift it over when I'm pulling the trailer? (Probably not ideal but just a thought...
When trying to work out what the effect of a change of gearing would be Sheldon Brown's Gear Calculator is incredibly useful. Just enter your current gearing, and the new gearing you're considering, and it'll calculate the results of each combination. It'll output in gain ratios, gear inches, metres development or (my personal favourite) bike speeds for a given cadence (rpm).
It should include both crank arms and the crank axle between them.
It's a standard road compact double crankset, so almost all road bike front derailleurs designed for doubles would shift it fine. You'll want one designed to be used on flat bar road bikes though, because then it will work properly with MTB style twist grip or trigger shifters. I'm not sure if the Freerider V2 had the same front derailleur braze on as Sofrider V2s but if so then you want the braze-on variety instead of a clamp on front derailleur.
The manual shifting you describe would work I think, but I'm pretty sure that after only a couple of dirty, fiddly hand shifts you'd be completely fed up with that approach and decide you should have bought a derailleur afterall... :roll:
MailSeanBell
Active Member
Thanks for the feedback hotdog.
I'm debating between working more on the bike, or working on the 'engine'... haven't worked the legs this much in a long time and the experience of riding seems to be changing daily.
I'm debating between working more on the bike, or working on the 'engine'... haven't worked the legs this much in a long time and the experience of riding seems to be changing daily.
Doug Burton
Zen MBB Master
Hi Sean,
This will work very well as a Freerider V2 upgrade, and I'll tell you why I know.
A couple of months ago it became painfully clear that our demand for Sofrider V2's was running considerably ahead of our production schedule (This is a good problem to have, but a problem nonetheless). As a short term market test, Maria, Jim and John asked me to develop an upgrade for the Freerider that would take it up to the Sofrider V2 drivetrain spec.
The principal issue other than labor cost and guaranteeing assembly/adjustment quality was that we couldn't source good quality chainrings to fit the 130mm crank spider on the Freerider at reasonable cost. The resulting test bike worked perfectly except the non-ramped-and-pinned 50t top chainring didn't shift like I thought a $1000 bike should shift, and the smallest low ring I could put on the 130mm spider was 39t, so the low gear benefit was less than we would have liked.
If I had known about this 155mm/50/36 crankset, we'd have built 20 Freerider V2.5's.
All that being said, I have a parts list for the rest of the parts required to complete this conversion, and I know it works because there's one sitting in my garage that I've ridden around the neighborhood several times. If I can get it to load at Photobucket, I'll post the testing video I made to analyze the shifting.
Additionally, I have 4 additional parts sets that I bought to build the remaining test bikes. These "kits" would convert an FRV2 or SRV1 to SRV2 drivetrain specs if used with that crankset.
Interested to know if there's any interest in this sort of "pre-tested Upgrade".
Thanks,
This will work very well as a Freerider V2 upgrade, and I'll tell you why I know.
A couple of months ago it became painfully clear that our demand for Sofrider V2's was running considerably ahead of our production schedule (This is a good problem to have, but a problem nonetheless). As a short term market test, Maria, Jim and John asked me to develop an upgrade for the Freerider that would take it up to the Sofrider V2 drivetrain spec.
The principal issue other than labor cost and guaranteeing assembly/adjustment quality was that we couldn't source good quality chainrings to fit the 130mm crank spider on the Freerider at reasonable cost. The resulting test bike worked perfectly except the non-ramped-and-pinned 50t top chainring didn't shift like I thought a $1000 bike should shift, and the smallest low ring I could put on the 130mm spider was 39t, so the low gear benefit was less than we would have liked.
If I had known about this 155mm/50/36 crankset, we'd have built 20 Freerider V2.5's.
All that being said, I have a parts list for the rest of the parts required to complete this conversion, and I know it works because there's one sitting in my garage that I've ridden around the neighborhood several times. If I can get it to load at Photobucket, I'll post the testing video I made to analyze the shifting.
Additionally, I have 4 additional parts sets that I bought to build the remaining test bikes. These "kits" would convert an FRV2 or SRV1 to SRV2 drivetrain specs if used with that crankset.
Interested to know if there's any interest in this sort of "pre-tested Upgrade".
Thanks,
defjack
Zen MBB Master
Got a ride today with the cranks and they are nice. I have a 11-32 and they climb ok with a 11-34 would be even better. They are ramped and pined so shift very good. I ended up using the rear wheel from the Cannondale as the the wheel I had on the Giant not only had cracked races but broken cones. Jack
