Bicycle Mechanics - Building a Custom Cassette

I have 2 new cassettes a Sram SR-PG830 (11x32) and a Nasbar NS-CST8 (11x28). The Sram is 11, 12, 14, 16, 18, 21, 26, 32, and the Nasbar is 11, 13, 15, 17, 19, 21, 24, 28. I want to drop the 12 & 26 out of the Sram and add the 24 & 28 from the Nashbar in between the Sram 21 & 32. Since the Nashbar 28 is the last gear is there a problem making it the next to the last gear in the new custom set? Any other problems in doing this? My rear derailleur will handle the 11-32 combo.

Never done it but I don't see why it wouldn't work. Worst case, you can always take the cassette back apart and return it to original.

If all of the cogs are loose, and the same thickness, then it will at least fit the hub, but you may find that differences in the radial timing results in poor shifting between the mismatched cogs.

DaveSSS,
Would the differences in the radial timing occur because of the 2 different brands?

Would the differences in the radial timing occur because of the 2 different brands?

The ramps of one cog won't necessarily line up with the profiled teeth of the next cog. With HyperGlide, a cassette is designed as a unit and mixing and matching cogs may degrade shifting. For most situations, the degradation isn't that much and may not even be noticable.

Here are some other issues you may run into...

1) The largest cogs (usually five with 8-speed) may be bound together with small screws. One of the cogs(probably the 16) will have threads for the screws. You are trying to add more cogs between this threaded cog and the largest cog and the screws will no longer be long enough. Doesn't really matter, though, as you can just put all the cogs on loose without the screws (or screw only the 16-28 together)

2) The 2nd cog on some cassettes that start with an 11 has a recess for the top cog. You may not be able to drop the 2nd cog out of the cassette.

3) You could also try mixing/matching to get an 11,13,15,18,21,24,28,32

DaveSSS,
Would the differences in the radial timing occur because of the 2 different brands?


It's not the brands as much as it is the difference in the number of teeth between adjacent cogs. The timing is different if the jump is 1-2 or 3 teeth.

I've done the "custom" thing with lower end Shimano 7 speed cassettes.
I started with a-
12-14-16-18-21-24-28 and a
13-15-17-19-21-23-26 to make a
13-14-15-16-18-21-24.
When I went to 8 speed, I simply "thinned" the spacers and used the 7 speed cogs, making a
13-14-15-16-17-19-21-24.
The smaller difference in adjacent cog tooth counts made up for any "perceived timing issues".
Since you will only have 4T changes between the largest cogs, instead of 5 & 6, those may actually shift smoother.
I bought a 2nd position 13T cog, since the 13T cog top cog wasn't supposed to work in the 2nd position. I didn't need to! (Summer I go to a 12-13-14-15-16-18-21-24)

The only problem I see is the huge jump between 11 & 14.
I simply would have bought a Shimano "P" which is a-
12-14-16-18-21-24-28-32 or-
the Nashar 12-13-15-18-21-24-28-32

I appreciate the information. I visited the Sheldon Brown website before launching out on this idea, and ran his calculator to study the different gear combinations, and read all the information he had. I’m trying to put together a gear combination that will allow me to pull some of the hills where I live. I’m not strong young man, so I have to do it with gears. I’m going to customize the cassettes, and will let you know what happens.

Bill where could I find a Shimano "P"?

Twice, I've cut up cassettes to create an 11x28, and it has worked just fine. Do it.

When mixing Sram with Shimano cogs, I ran into shifting problems that I have eventually tracked down to the different profiles of teeth in the direction of thickness of the cogs, for Sram and Shimano. When adjusting the tension in the cable, I was getting indexing consistent with the chain getting caught by the tips of cogs for either Shimano or Sram, but not for both at once. I have eventually drifted to Shimano only. Another option was to adjust the thickness of spacers at interfaces between brands.

Bill where could I find a Shimano "P"?

Have you checked to see if your LBS can get it?

Not a Shimano, but the Forte comes with the same cogs as the "P" for $17 at Performance Bike-
http://www.performancebike.com/shop/profile.cfm?SKU=11470&subcategory_ID=5130

Bill,
I'm a newbie to bikes, and not an authority on brands. Is the Forte a good cog component?

Bill,
I'm a newbie to bikes, and not an authority on brands. Is the Forte a good cog component?

Nothing wrong with it. It may not have the latest technology, or be the lightest, but it will do the job and hold up well enough for most folks. If price is a factor, go for it.

For $17??
You could drop the 11, 12 & 26 from the SRAM, use the 12T from the Forte and the 24-28 from the Nashbar..

IF you wanted tp get "crazy". you could pick up a 13-23 and you'd have enough cog selection to make bout any custom combination you'd ever need. Handy if you wanted to switch between Mountain & Road type use.

With the 2 cassettes I used in my original post, I can make a combination of 12 or 13 through 19 with 1T increments + 21, 23, 24, 26 & 28.
My riding is all flat, city type, although I still have the granny ring if I were to need it.
It's nice to be in "cruise mode" and be able to shift up/down 1T as the head wind changes. It allows me to keep my cadence in a very narrow range that works best for a decrepit old man!
I've been recently "experimenting" with different length cranks/rings, so I can rather quickly, change the cogs to "fine tune" my gearing.

I was thinking the same thing. It may be better to start your cassette(s) with a 12 or a 13 allowing closer ratios on the rest of the cassette.

Al

I've got my new cassette on, and it shifts great. I use the 12T from a Shimano 12-23 for my first cog. I droped the 11, 12 from a new Sram 11-28, and added a 12T Shimano for the first gear (I had a good like new Shimano 12-23 cassette). I took the 32T from a new Sram 11-32, and made it the last gear of the new cassette. Now the new cassette is geared like a Shimano "P". Why I didn't do as Bill said and buy the Shimano "P", or Nashbar 12-32. I could not find either at the present time, and I wanted to get to riding. Nashbar was out of the 12-32.
I'll keep looking beacuse I want to set up another wheel.
Thanks for the information on Forte, I'll go ahead and order one to see how it does.
I appreciate all the good input.
Now I'm thinking about a new project. I have installed a new Shimano R600 compact crank (34-50). It has a cbd of 110mm. I would like to replace the 50T ring with a 52 or 53. Any thoughts?

I've got my new cassette on, and it shifts great. I use the 12T from a Shimano 12-23 for my first cog. I droped the 11, 12 from a new Sram 11-28, and added a 12T Shimano for the first gear (I had a good like new Shimano 12-23 cassette). I took the 32T from a new Sram 11-32, and made it the last gear of the new cassette. Now the new cassette is geared like a Shimano "P". Why I didn't do as Bill said and buy the Shimano "P", or Nashbar 12-32. I could not find either at the present time, and I wanted to get to riding. Nashbar was out of the 12-32.
I'll keep looking beacuse I want to set up another wheel.
Thanks for the information on Forte, I'll go ahead and order one to see how it does.
I appreciate all the good input.
Now I'm thinking about a new project. I have installed a new Shimano R600 compact crank (34-50). It has a cbd of 110mm. I would like to replace the 50T ring with a 52 or 53. Any thoughts?

Sounds like a good way to partially offset the loss of the 11T sprocket.
The shifting will be less smooth on the fder with the bigger jump though.

....
Now I'm thinking about a new project. I have installed a new Shimano R600 compact crank (34-50). It has a cbd of 110mm. I would like to replace the 50T ring with a 52 or 53. Any thoughts?

Almost snorted my soda through my nose!:)

You've already got a 16T difference between rings, so shifting will definitely get worse.
Maybe time for some combination of an 11-30 cassette?

But really, with a 50/12 top gear, maybe you need to work on cadence a bit?

I learned in racing boats, motorcycles, and cars that you gear for the engine. Being a 64 out of shape newbie, my engine does not make a lot of power. I'm working on this daily to increase the horse power. It's a balancing act between sore, and tired. I'm trying to lose weight so keeping the carb intake down results in tired. Upping carbs results in sore. I have a 38 year old son who is in great shape and been riding for 8 years. He has me on a program. Indoor this winter with my bike on a trainer doing 100 cadence intervals for an hour of hell twice a week. Two other days I lower the resistance and ride to get heart rate up to about 130 for another hour. Two other days I work out on my rowing machine. The last day is upper body strength training. This has been program for last 3 months. It's been tough, but am losing weight, and blood pressure is better.
I appreciate the help and advice that you have given me. THANKS!

I guess that answers the cadence issue!:)
I'm 3 years younger and can't get my chubby legs close to 100. A bad knee doesn't help either.
That's the main reason I got into customizing my cassette. With 55 years of smoking, my lung capacity isn't the greatest, but I've found if I keep my cadence within a narrow range of about 5 RPM, I have my best stamina. Being able to shift to a 1T different cog works great when the head wind changes slightly. Also when experimenting with different crank lengths, I could change the gearing for a "best fit".
I ride a "commuterized" 86 RockHopper, so I do have a triple, but I pretty much use it as a 1x8 on the middle (38) ring. I need a good tail wind before I even think about the big ring.
I have to ride very upright because of a bad back, so a head wind kills me!

I guess the question I'd ask is, are you spinning out with the 50-12 combo and "how often"? Going to a 53T ring would raise your top speed from about 32 to 34 MPH.
IF this is for downhill speed, wouldn't it be better to rest, so you have more "in the tank" for the next up hill?

A 50-12 combination is plenty high enough for most of us.

I don't spin in the 50/12 combo, but have done 2 & 3 minute intervals at 100 rpm in the 50/14. It's a killer to me. Normal warm up spin at 100 rpm is in the 34/18, then do different intervals in shifting to 50 ring, then drop back to 34 and upping to 16 cog, back up to 50, then drop back to 34 and upping to 14 cog, and back up to 50 ring. Then working back down to finally getting back to 34/18. This is an hour work out. My son dreams up all this torture.
Until I get back out on the road, I'm going to leave everything the way I've got it.
If I need more HI end for the down slops, then I'll switch the 12T with an 11T.
I was just wanting to check with you about the possibility of going bigger on the ring.
Thanks for all the good input.

My highest combination on my road bike is a 52/11. I use it maybe twice a year.

Why do I keep it, you ask?

Becasue when I do get a chance to use it, it's a blast! ;-)

I don't spin in the 50/12 combo, but have done 2 & 3 minute intervals at 100 rpm in the 50/14. It's a killer to me. Normal warm up spin at 100 rpm is in the 34/18, then do different intervals in shifting to 50 ring, then drop back to 34 and upping to 16 cog, back up to 50, then drop back to 34 and upping to 14 cog, and back up to 50 ring. Then working back down to finally getting back to 34/18. This is an hour work out. My son dreams up all this torture.
Until I get back out on the road, I'm going to leave everything the way I've got it.
If I need more HI end for the down slops, then I'll switch the 12T with an 11T.
I was just wanting to check with you about the possibility of going bigger on the ring.
Thanks for all the good input.

Is your son trying to "get even" with you for something?:)

I think it's a good idea to do some actual riding to see how things work out. I'm guilty of doing all my gear calculations on a spread sheet to see "what if". It's easy to get so carried away, that when you actually implement it, you end up wondering "what was I thinking"!
The good part is that you get so adept at customizing your cogs, it's a quick job to change to some other combination.

I'm not a big fan of swapping the chain rings, since that entails moving/readjusting the FDER to do do ir "right". Plus, I don't like putting a new "kink" in the FDER cable each time.
It's much simpler to do the rear, IMO.

... I have a 38 year old son who is in great shape and been riding for 8 years. He has me on a program. Indoor this winter with my bike on a trainer doing 100 cadence intervals for an hour of hell twice a week. Two other days I lower the resistance and ride to get heart rate up to about 130 for another hour. Two other days I work out on my rowing machine. The last day is upper body strength training. This has been program for last 3 months. It's been tough, but am losing weight, and blood pressure is better.
It sounds as if your son wants to keep you around - you are a truly lucky man! And congratulations to you for rising to the challenge. Keep up the great work!
One thing though - trainers don't give you the same kind of feedback that riding on terrain would - so don't be too eager to go to a larger chainring! You will find your engine may respond differently to foad conditions - especially hills.
You are four years my senior - if your knees and hips are in perfect shape, then higher gears are not too bad - but I think that once you get out on the road, you will get into a different training regimen in order to build up your stamina at different cadences and grades. I've been riding for 38 years, and for a long time used higher gears than I should have - now, I've got a bad knee that forces me to go more gently and that has taught me the benefit of dropping to a lower gear and spinning. Take it gradually and build up your strength and stamina as you learn the ropes. I hope you have many rewarding years of riding!

I emailed Sheldon Brown that "I have installed a new Shimano R600 compact crank (34-50). It has a CBD of 110mm. I would like to replace the 50T ring with a 52T or 53T. Will the TA 110 Outer Chainring in 52 Teeth (CRT052), or 53 Teeth (CRT053) work, and any potential shifting problems? Any thoughts?"
His reply, "Yes, the TA rings will work. Shifting crispness may suffer slightly depending upon the shifters used. But the shifting performance will still be perfectly acceptable unless you are in elite level competition."

Thanks for encouragement and advice. I'm looking foward to getting back outside, maybe with in the next month.

Hello -

It sounds like there are a lot of folks on this thread with the expertise I am looking for so I hope you don't mind if I jump in with a similar question. I am an older Pennsylvania tandem touring rider looking for a custom 9-speed Shimano hyperglide cassette with much closer spacing in the range I ride in mostly. My "dream" cassette is a 15-17-19-21-23-25-27-30-34.

We ride heavily, but I never use anything above the 15 tooth ring, and if I did, my wife would be screaming to slow down so I may as well put the gears where I can use them. Also, on a tandem I can't hear anything way back there anyway, so a little clicking does not bother me at all as long as the shifting performance has a reasonably smooth feel.

I have the following questions:

(1) Any mechanical problem with a 15 tooth top end on a Shimano 9-speed cassette?

(2) If I get the parts, is this something anyone with reasonable mechanical skills (me) can put together without too much trouble?

(3) Are there multiple versions of some sprockets designed with different ramps for transition from different gears (17 to 19 vs, 17 to 20 for example) or are all hyperglide 20 tooth 9-speed sprockets the same?



Thank you all so much!

Don

Hello -

It sounds like there are a lot of folks on this thread with the expertise I am looking for so I hope you don't mind if I jump in with a similar question. I am an older Pennsylvania tandem touring rider looking for a custom 9-speed Shimano hyperglide cassette with much closer spacing in the range I ride in mostly. My "dream" cassette is a 15-17-19-21-23-25-27-30-34.

We ride heavily, but I never use anything above the 15 tooth ring, and if I did, my wife would be screaming to slow down so I may as well put the gears where I can use them. Also, on a tandem I can't hear anything way back there anyway, so a little clicking does not bother me at all as long as the shifting performance has a reasonably smooth feel.

I have the following questions:

(1) Any mechanical problem with a 15 tooth top end on a Shimano 9-speed cassette?

(2) If I get the parts, is this something anyone with reasonable mechanical skills (me) can put together without too much trouble?

(3) Are there multiple versions of some sprockets designed with different ramps for transition from different gears (17 to 19 vs, 17 to 20 for example) or are all hyperglide 20 tooth 9-speed sprockets the same?



Thank you all so much!

Don


PS - My apologies if I have double posted this...

1) Yes. Shimano cassettes always have a built-in spacer on the top cog and I don't think any of the Shimano 9-speed cassettes use a 15 that has built-in spacer. The reason a built-in spacer is required is so that the cog will engage enough of the freehub splines. This is especially true if the freehub is a "compact" type where the splines don't go all the way to the end. (http://www.sheldonbrown.com/k7.html#hyperdrivec). But even if your freehub is not compact, I don't think it'd be wise to put on a top cog that doesn't have a built-in spacer, especially on a tandem where there are two motors generating torque. I believe the largest top cog in Shimano 9sp cassettes is a 14. However, the two 9sp cassettes I could find on techdocs.shimano.com (Ultegra http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/CS/EV-CS-6500-1680A_v1_m56577569830611831.pdf and Tiagra
http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/CS/EV-CS-HG50-9R-1880A_v1_m56577569830608763.pdf) show that many of the cogs come on carriers and cogs on carriers must be added and removed as a unit - i.e. you are very limited in customizing. I thought that the 105 9sp cassette didn't use cog carriers but that's not on techdocs and I don't happen to own a 105 9sp cassette so I don't know for sure.

2) Yes. The difficult part will be finding cassettes and cogs that will work and give you what you want.

3) Yes. HyperGlide cassettes are designed to be used as a unit and the 15 that is part of a 12-23 is different than the 15 that is part of a 12-27. However, there's usually not a noticable difference when you mix and match between different range cassettes. I've done it plenty of time.

I've mixed Shimano Ultegra, D-A, and XTR cogs to build custom 9-speed cassettes with good results. The XTR that I used was a 12-34. 12, 14, 16, [18-20] [23-26] [30-34] The larger cogs are pinned together on common carriers and cannot be used separately. From this cassette and other parts I built a 13-26, my favorite 9-speed cassette. At one time I had my wife on a 14-28 9-speed.
I cannot detect any shifting degradation mixing Shimano cogs, but I always try to keep the ratios as close as possible and still get the job done.
I definitely would not try to run a crankset with anything bigger than a 50 with a 34 inner ring. That would be like shifting a car from 2nd gear to 6th gear, the engine would probably die. I hate big ratio jumps and corresponding cadence jumps. I run a 53-39 crankset but would rather have a 52-39 or 50-36.

Al

A 50x12 high gear is 112 gear-inches and 80 rpm will give you 27 mph and 90 rpm will give you 30 mph . Can you really ride that fast on anything but a downhill?

Years ago, the Tour de France was won on lower top gears. I remember reading Steven Roche's book where he said how happy he was to get a freewheel with a 13T small cog. Previously they only had a 14T available. That gave him a 52x13 or 108 gear-inch high gear and he won the '87 Tour using it.

There's nothing wrong with mix and matching cogs as needed. i've been doing this since cassettes became popular in the mid 80's and here's a few things i've learned.

1. If the lower cogs are riveted or screwed together the the rivets can grinded off and the screws can be removed with NO adverse consequences.

2. In many cases the first 2 high gear cogs can NOT be easily interchanged due the their built in spacers.

3. If NON matching cogs are swapped out i.e. a P for a Q or a Q for an R shifting quality will be diminished but is still going to be better than the old uniglide days.

Its easier and cheaper to start with a cassette that has the high gear cogs you need.

Miamijim is right about mixing. The cassette that I am now using (12, 14, 16, 18, 21, 24, 28, 32) is made from 3 different sets, a Shimano (12-23) for 12, Sram #1 (11-32) for 14, 16, 18, 21, Sram #2 (11-28) for 24, 28, and Sram #1 (11-32) for 32. All 3 cassettes were 8 speed, so cogs and spacers were all same thickness. Since neither of the Sram cassettes lowest 3 gear were on a spider, I simply separated all 3 cassettes. One had 3 long screws holding it together which I removed, and 2 had 3 long rivets which I dremeled the heads off and removed them. I did not have to use any thing for the new cassette. I simply put the cogs and spacers onto the hub freewheel. It is the best shifting cassette I've ever used. I would not want to have more than a 4 tooth difference in the cogs. I'm also using a compact crank (50/34). I replaced the 53/39 crank on my 1996 Trek 5000 OCLV. The front derailleur is the original Shimano, but I replaced the rear derailleur with a Shimano RD-M580-SGS (Long Cage). I can use all cogs with the 50T Ring without chain rubbing the front derailleur, and all cogs except the 12T with the 34T Ring. Cross chaining is not go for chain or gears, so I stay away from the 28T & 32T while in the 50T Ring, and the 12T & 14T while in the 34T Ring. That said all shifts are rock solid and instant no matter what Ring-cog combination. You will also need to get a few good bike specific tools. Hope this helps. Good luck, and don't be afraid to try things. You can always work it out, and the guys on this forum are the best, that is how I learned a lot.