Well who knew?

[karlboss]

I put Sram Rival on my new bike, broke a shift lever in a way I didn't think a lever should ever broke, put the pics up somewhere else. In trying to find a solution I happened upon an article by lennard zinn http://velonews.competitor.com/2008...ers-with-a-sram-drivetrain-sure-why-not_73404, saying 10 speed campag was compatible with Sram. So as centaur levers were cheaper than rival I thought I'd give it a shot and if it failed convert to full Campy. Works fine. Great infact, and allows me to run my 11-28 cassette. I doubt I've helped resale value, but happy for now. We'll see how it goes over time.

 

[JA.Tri]

Cool info... Central Index?

Be great to have a central index for all info like this.

Note: not that I currently use either SRAM or Campy...none the less very useful info and I am sure there is plenty more such like floating in the "ether".

js

 

[Bustedknuckle]

I put Sram Rival on my new bike, broke a shift lever in a way I didn't think a lever should ever broke, put the pics up somewhere else. In trying to find a solution I happened upon an article by lennard zinn http://velonews.competitor.com/2008...ers-with-a-sram-drivetrain-sure-why-not_73404, saying 10 speed campag was compatible with Sram. So as centaur levers were cheaper than rival I thought I'd give it a shot and if it failed convert to full Campy. Works fine. Great infact, and allows me to run my 11-28 cassette. I doubt I've helped resale value, but happy for now. We'll see how it goes over time.

Yep, he showed me this conversion right after he did it. Campagnolo 10s ERGO, sram RD, shifts shimano/sram 10s spacing, pretty slick. And when the RD goes south, get a Campag one, and a Campag 10s rear wheel.

BUT ya could have warrantied those that shifter. sram will warranty anything for any reason at any time..cuz they know the designs have problems and it's really inexpensive, regardless of how expensive it may be retail.

BT getting Campagnolo levers are far better, longer term solution. Bravo!

 

[karlboss]

Yep, he showed me this conversion right after he did it. Campagnolo 10s ERGO, sram RD, shifts shimano/sram 10s spacing, pretty slick. And when the RD goes south, get a Campag one, and a Campag 10s rear wheel.

BUT ya could have warrantied those that shifter. sram will warranty anything for any reason at any time..cuz they know the designs have problems and it's really inexpensive, regardless of how expensive it may be retail.

BT getting Campagnolo levers are far better, longer term solution. Bravo!

I bought the shifters from a guy who won them in a competition...no warrranty for me. I did have some other ways to find a cheap sram shifter, but after hearing some opinions here and the way it broke I didn't have any confidence in sram.

 

[Fatclimber]

From the article:

I did measure the difference in cable pull between SRAM and Campy 10-speed shifters. Nine clicks of a Campy lever pulls 27.0mm of cable, or 3mm per click. Nine clicks of a SRAM lever pulls 27.9mm, or 3.1mm per click. Jtek’s adapter may adjust for this minuscule difference, but in my experience, it works perfectly with no adapter.

The difference between the two is 3 1/3% which would add up to 30% difference by the time you shifted through all your gears. Of course you could align it in one of your middle gears during your initial setup but that would still leave a 15% difference at your outside cog. Leonard says it works "perfectly," but knowing it was off that much would drive me nuts. If you ever have your chain off, shift through your gears and you will see.

I've been using Campy shifters with Sram rear derailleur and cassettes for a few years now. I installed one of the J-tek shiftmates that he references in the article and it aligns nicely across all the gears.

Sram cassettes are notorious for being noisy, so if you don't hear anything it must be working well.

 

[ElChingon]

Some of you's are just noticing these things. It has always worked even if by work meaning you got some pre-shift or post-shift jumps. Sure sometimes its not perfect but you can use any shifter for any derailure/cogset brand. Ever wonder what happens when a Pro gets a flat and the team car is no where near by and the neutral support doesn't have the correct brand cassette wheel (if its a rear flat)? Yea, they've always just mounted the wheel and the rider rides on till the team car is close enough to do a proper change if not finish the race/stage. You didn't think the rider would just sit there and wait for correct brand wheel did you?

 

[karlboss]

Some of you's are just noticing these things. It has always worked even if by work meaning you got some pre-shift or post-shift jumps. Sure sometimes its not perfect but you can use any shifter for any derailure/cogset brand. Ever wonder what happens when a Pro gets a flat and the team car is no where near by and the neutral support doesn't have the correct brand cassette wheel (if its a rear flat)? Yea, they've always just mounted the wheel and the rider rides on till the team car is close enough to do a proper change if not finish the race/stage. You didn't think the rider would just sit there and wait for correct brand wheel did you?

Noticing? no, using yes. I haven't experienced any pre or post shift jumps yet, and my first few rides I've thrashed it. Will see how it goes.

 

[kiwirider]

The difference between the two is 3 1/3% which would add up to 30% difference by the time you shifted through all your gears. Of course you could align it in one of your middle gears during your initial setup but that would still leave a 15% difference at your outside cog. Leonard says it works "perfectly," but knowing it was off that much would drive me nuts. If you ever have your chain off, shift through your gears and you will see.

Your logic is off there ...

If you were right, you'd still be at about cog 7 when you'd shifted all the way across the block - since 30% is approximately 1/3 of the total shift.

The thing that you're missing is that, while the total difference in shift distance is increasing, the proportion isn't.

So, for the first shift - Campag does 3mm, SRAM does 3.1mm - difference = 0.1mm or 3.22%

For the second shift - actual shift is the same as for first shift.
Total shift - Campag - 6mm; SRAM - 6.2mm - difference = 0.2mm or 3.22%

... and so on ...

 

[karlboss]

Your logic is off there ...

If you were right, you'd still be at about cog 7 when you'd shifted all the way across the block - since 30% is approximately 1/3 of the total shift.

The thing that you're missing is that, while the total difference in shift distance is increasing, the proportion isn't.

So, for the first shift - Campag does 3mm, SRAM does 3.1mm - difference = 0.1mm or 3.22%

For the second shift - actual shift is the same as for first shift.
Total shift - Campag - 6mm; SRAM - 6.2mm - difference = 0.2mm or 3.22%

... and so on ...

and halved if you adjust to a middle cog instead of end, I can handle being no more than .45mm of cable pull out.

 

[Fatclimber]

Your logic is off there ...

If you were right, you'd still be at about cog 7 when you'd shifted all the way across the block - since 30% is approximately 1/3 of the total shift.

The thing that you're missing is that, while the total difference in shift distance is increasing, the proportion isn't.

So, for the first shift - Campag does 3mm, SRAM does 3.1mm - difference = 0.1mm or 3.22%

For the second shift - actual shift is the same as for first shift.
Total shift - Campag - 6mm; SRAM - 6.2mm - difference = 0.2mm or 3.22%

... and so on ...

My logic isn't off, but maybe the explanation is.

You're right, the ratio remains the same relative to number of shifts and distance from the smallest cog, however the length of offset between center of cog and center of upper jockey pulley will increase by .1mm after each shift. This is the ratio I was referring to.

.1mm / 3mm = 3 1/3%

after 7 shifts the offset would total .7mm

.7m / 3mm = 23 1/3% **This is what I was referring to, not the .7mm / (7 * 3mm) = 3 1/3%**

By the time you shift all the way over to the largest cog, you will have shifted 9 times for a total of 27mm and perfect alignment would require 27.9mm. You are .9mm out of alignment. Sure, that's only 3 1/3% off the overall shift distance but I'm not concerned with that nor is it what I was referring to. Being .9mm off alignment when it is only 3mm between cogs is becoming a significant factor(30%).

Nine tenths of one millimeter isn't going to make or break your shifting. But who knows, maybe after a little cable stretch finally becomes noticeable it could be at an inopportune time and you might not be able to get into the biggest cog when you really need it.

 

[kiwirider]

Longer explanation

Ok, that makes more sense ... but while I'll agree with your maths, I'd still disagree that they translate into the mechanics in the way that you suggest. Factors like cable stretch, where the derailleur finally rests after a shift, tendencies to over/under shift, impact of chain tension, alignment of derailleur hangers, number of gears shifted at one time, etc., etc. mean that I'd don't believe that you get that linear relationship that the maths show.

Regardless of that - check out what you're actually talking about as a distance out across the entire block.

If you're really good, you can draw it using a ruler (or better still, get a 0.9mm pen or pencil and put a dot on the page). If not - and unless you have a micrometer - a rough and ready way of visualising the distance is as follows:
open a document and put a dash/minus sign in it - or any other "full space" character (ie., not thin characters like i, j, l, etc);
set the font size for that character to 12 point;
print it;
take a quarter of the line ...

That's 0.9mm (actually it's a bit more - 1pt = 0.35mm - but for current purposes we're talking near enough) ...

And if you tune the gears in the middle of the block as Karlboss suggested, you halve that ...

Kinda talking about two parts SFA ... I can assure you that my derailleur hanger on my cyclocross bike and MTB are both out by way more than that across the entire block - and that doesn't affect my shifting ...

 

[Fatclimber]

Ok, that makes more sense ... but while I'll agree with your maths, I'd still disagree that they translate into the mechanics in the way that you suggest. Factors like cable stretch, where the derailleur finally rests after a shift, tendencies to over/under shift, impact of chain tension, alignment of derailleur hangers, number of gears shifted at one time, etc., etc. mean that I'd don't believe that you get that linear relationship that the maths show.

Regardless of that - check out what you're actually talking about as a distance out across the entire block.

If you're really good, you can draw it using a ruler (or better still, get a 0.9mm pen or pencil and put a dot on the page). If not - and unless you have a micrometer - a rough and ready way of visualising the distance is as follows:
open a document and put a dash/minus sign in it - or any other "full space" character (ie., not thin characters like i, j, l, etc);
set the font size for that character to 12 point;
print it;
take a quarter of the line ...

That's 0.9mm (actually it's a bit more - 1pt = 0.35mm - but for current purposes we're talking near enough) ...

And if you tune the gears in the middle of the block as Karlboss suggested, you halve that ...

Kinda talking about two parts SFA ... I can assure you that my derailleur hanger on my cyclocross bike and MTB are both out by way more than that across the entire block - and that doesn't affect my shifting ...

That's fine if you feel that way about this, it never was part of the discussion.

Thanks for helping me visualize what .9mm looks like. Not necessary as I actually had a caliper sitting next to me at the table.

Thanks again, but if you read my first post on the subject, yep, the first one your quoted from, you will see that once again I agree wholeheartedly.

That's great, I hope they continue to work well for you. And the OP already said he is satisfied so far with how his rear derailleur is functioning. I never said it wouldn't work.