Rear cassette reordering problem with CYC Photon, derailleur touching some sprockets

Clouseau

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Hello all, I have converted my bike to Cyc photon motor kit and wanted to rework a new cassette for it because old one was done. The cassette is 11-39t size, its a 10 speed bike so is the cassette, gradation is: 11-13-15-17-20-23-26-30-34-39

I was going with 11-13-17-23-30 which will be used for shifting, and others that will not be used are just put on the cassette so it can fit a wheel for proper spacing. But derailleur is touching sprocket 30 and cannot shift becase the 30 sprocket is closer to it. I tried the 26 instead and it has the same problem. In the end I was able to remove 15 and now I have: 11-13-17-20-23-26-30-15-34-39. I cannot use anything above 23 due too much angle on the chainline. The bike picture is attached. The problem is in that part that is angled on which the wire from the shifter attaches, check picture attached. The derailleur is SLX. Can I fix this somehow with a different 10 speed derailleur that doesn't have that wire holder angled but straight on the case of derailleur? Can I change a hanger to someting else that will give me more clearance? Maybe something like an extension on hanger, will that fit to this type of derailleur and current hanger?
 

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Did you try to adjust the "b" screw on your derailleur; FME, that's its purpose. Barring that you can get enough gears and an acceptable chainline with a custom "cassette". For years I used 11-17-28 spaced 8-speed on my BBS02-equipped conversion and found it adequate for all conditions in socal.
 
Did you try to adjust the "b" screw on your derailleur; FME, that's its purpose. Barring that you can get enough gears and an acceptable chainline with a custom "cassette". For years I used 11-17-28 spaced 8-speed on my BBS02-equipped conversion and found it adequate for all conditions in socal.
I did, not helped.

A derailleur dropper cheaper than a new derailleur.
Yeah, I have found out that option after I posted here.
Can that fit on my current hanger?
 
Yeah, the hanger extensions are universal fit, no issues there. Most are way too long ... typically you're only looking for <20mm extension, and most exceed this. There's stocky little ones from Chinese web stores that serve the purpose, for a couple of dollars.

Your B screw isn't wound in on the photo you posted. I presume you did wind it all the way in. You can use a longer B screw (up to 10mm longer is possible with some derailleurs), to the point where the angle of attack means the screw misses it's target. (It's obvious when this occurs, do it and you'll see for yourself). There's still more for the taking though, by broadening the screw so that it can wound in further without missing the target. This is achieved either via a nut on the screw end, or by reversing the screw (threading it in backwards) so that the breadth of the screw head achieves the same objective. They're M4 thread if you need to source a longer one.

Lastly, yes, there's many derailleurs you could use that "doesn't have that wire holder angled but straight". It doesn't even have to be ten speed, with shimano you could use a 9sp one if it's more suitable.
 
I tried to screw it all in :D but not helped. It doesn't affect that much, it moves 1-2mm it from the 30 sprocket, when the cassette is reordered. Stock cassette works fine, shifts to all gears. I will go with extendension for the hanger, will check it out. Btw does this part come off and can be replaced with an extension or do I need to attached it to the current one?
 

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Leave that as is - it bolts to hanger extension, hanger extension bolts to frame hanger.

Hanger extension is the least preferred method though, worse than B screw winding.

It'll make the bottom of the cassette shifts worse. And you've already compromised the cogs' ramp and off-ramp alignment, so upshifts will be clunky, and you can no longer make clean double or triple shifts.

(The alignment related shift performance you can slightly improve by reorienting the cogs so that the ramps line-up better. You can't get them perfect, but can improve it. It's easy enough with Shimano splines despite their non-symmetry - most of the splines line-up whichever way you locate cogs, so only minimal grinding/filing is required.

But you shouldn't require the hanger extension or extra long B screw. If you must have the 30T, you should put the 26T in front of it instead of the 23T, and widen the tooth jumps lower down the cassette. So, 30-26-20-15-11.

The 26 to 30 jump has to work without clearance issues, because it's a native jump already built-in to the cassette.
 
I have to use 11T and 13T because 11T sprocket is molded that way that it fits into 13T. 15T and above are the same. And that last screw ring fits into 11T. I have tried 11-13-17-20-26 and the chain also get stuck in that "angled wire holder" when I shift onto 26T. So either hanger extender or a different derailleur. If I decide to downsize to 6 speed derailleur like Tourney and front shifter, can I leave 10 speed cassette and use only first 6 cogs from it or the cassette cogs spacing is different on 6 speed?
 
I have to use 11T and 13T because 11T sprocket is molded that way that it fits into 13T. 15T and above are the same. And that last screw ring fits into 11T. I have tried 11-13-17-20-26 and the chain also get stuck in that "angled wire holder" when I shift onto 26T. So either hanger extender or a different derailleur. If I decide to downsize to 6 speed derailleur like Tourney and front shifter, can I leave 10 speed cassette and use only first 6 cogs from it or the cassette cogs spacing is different on 6 speed?
Every different gear count has different spacing between sprockets. Shimano pattern derailleurs have the same cable pull ratio for 5, 6, 7, 8, and 9 speed systems; only the shifter differs substantially. 10, 11, and 12 speed systems each have their own cable pull ratios that are incompatible with other gear counts.

Roadbike-Cassette-1024x576.png
 
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This

Every different gear count has different spacing between sprockets. Shimano pattern derailleurs have the same cable pull ratio for 5, 6, 7, 8, and 9 speed systems; only the shifter differs substantially. 10, 11, and 12 speed systems each have their own cable pull ratios that are incompatible with other gear counts.

Roadbike-Cassette-1024x576.png
So I would also have to change the cassette to 6 speed? In the long run that would be a cheaper option for replacement parts though. But now I have brand new 10speed cassette :D
 
I have a hanger extension on one of my bikes, and even a replacement extended b screw. Definitely help with reaching a bigger cog when the cog is in the right place.

Reordering the cassette to have bigger cogs near the drop out is a tough ask from the derailleur, though. When a derailleur moves closer to the hub to reach bigger cogs, it doesn't just move horizontally, it moves down as well. So putting the big cogs closer to the drop out is missing the extra distance down the derailleur usually travels on the way there.

I suppose, technically, you might be able to slap a bunch of washers somewhere to mount the derailleur farther out from the drop out. You aren't planning to use the full range anyway, and spacing out farther out gives it more room to move down while it moves in. Then use the top set of gears on your shifter to instead of the bottom set for the range you want to access. I did that once, but it was a pain finding longer screws for the derailleur to fit the washers between it and the hanger. They are some bizarre extra fine thread size. And you have to be careful various things like the b screw still find a shoulder to push against.

I might try other solutions to a bad chain line before this, though. Like a higher speed chain is more flexible, adding a chain guide or tensioner can help, different bottom bracket or trying to get all the extra room on the bottom bracket to the other side of the bike, etc..

Have you considered just using a smaller tooth front chain wheel and then not needing such big cogs on the back? CYC seems to sell a variety of tooth counts:
 
So I would also have to change the cassette to 6 speed? In the long run that would be a cheaper option for replacement parts though. But now I have brand new 10speed cassette :D
There were very few 6 speed cassettes made, and they haven't been made in many years. 7, 8, and 9 speed cassettes are all much more broadly available, though 34 teeth is usually as big as 7 speed cassette sprockets get. 8 speed cassettes are available up to 46t at least, and 9 speed even larger.

If you substitute a derailleur of larger capacity, like for instance a Sunrace M9 that can shift sprockets up to 51 teeth, then you can use any Shimano type shifter up to 9 speed, with a cassette or partial cassette of the same gear count.
 
I have a hanger extension on one of my bikes, and even a replacement extended b screw. Definitely help with reaching a bigger cog when the cog is in the right place.
...
Have you considered just using a smaller tooth front chain wheel and then not needing such big cogs on the back? CYC seems to sell a variety of tooth counts:
I have 42T on the front due to a more flat rideing. I have low miles on Cyc but allready noticed it would be better for the chain if the I had 26 or 30T at the back which I couldn't use because the chain had too much of an angle. Cyc has recently released a "heavy duty drivetrain" Heavy-Duty Drivetrain | CYCMOTOR
It is not cheap but 15T smallest on the back is not friendly for flat rideing as leg cadance is pretty high..
 
There were very few 6 speed cassettes made, and they haven't been made in many years. 7, 8, and 9 speed cassettes are all much more broadly available, though 34 teeth is usually as big as 7 speed cassette sprockets get. 8 speed cassettes are available up to 46t at least, and 9 speed even larger.

If you substitute a derailleur of larger capacity, like for instance a Sunrace M9 that can shift sprockets up to 51 teeth, then you can use any Shimano type shifter up to 9 speed, with a cassette or partial cassette of the same gear count.
So I could use first 9 gears of my current 10 speed cassette? In the end I would use 5 but can I leave current cassette in a case I change to M9 and shimano 9 speed shifter? Current cassette is SHIMANO Cues LG400-10 11-39t because it is all steel made.
 
So I could use first 9 gears of my current 10 speed cassette? In the end I would use 5 but can I leave current cassette in a case I change to M9 and shimano 9 speed shifter? Current cassette is SHIMANO Cues LG400-10 11-39t because it is all steel made.
I said before that 10 speed has its own incompatible cable pull ratio, so it only works with both a 10sp shifter and a 10sp derailleur (which the Sunrace M9 is not).

Shimano CUES uses a unique sprocket spacing that isn't compatible with non-CUES systems. To make that work correctly, you'll need a CUES shifter and derailleur both.
 
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So I need to change cassette, shifter and derailleur :D For my current settup with SLX derailleur and deore shifter, could it be the problem that the new cassette is CUES and that is why I cannot put 30T sprocket on the fifth place and that is why it is to close to the derailleur in that spot? Should I have bought a nonCUES shimano 10 speed cassette and reorder that one?

EDIT: no, that makes no sense to me. You ment if I change to Sunrace. Shimano looking at your table for 10 speed is universal in their range so CUES-noCUES one the result would be the same. I think I will go with hanger extender and see how it goes, its 2 eur on ali so will check that first.

Thank you all :)
 
So I need to change cassette, shifter and derailleur :D For my current settup with SLX derailleur and deore shifter, could it be the problem that the new cassette is CUES and that is why I cannot put 30T sprocket on the fifth place and that is why it is to close to the derailleur in that spot? Should I have bought a nonCUES shimano 10 speed cassette and reorder that one?

10 speed SLX derailleur and 10 speed Deore shifter should be compatible. But note that your RD-M675 rear derailleur is rated for a maximum sprocket size of 36T. Even that might exceed the derailleur's capacity if you move it towards the middle of the freehub body rather than at the inside end.

That's why I was recommending Sunrace M9, which like more up-to-date Shimano MTB derailleurs is designed to work with larger sprockets. Unlike more up-to-date Shimano derailleurs, it's designed to work equally well with 5, 6, 7, 8, or 9-speed shifters (but not with 10, 11, or 12, and not with CUES).
 
10 speed SLX derailleur and 10 speed Deore shifter should be compatible. But note that your RD-M675 rear derailleur is rated for a maximum sprocket size of 36T. Even that might exceed the derailleur's capacity if you move it towards the middle of the freehub body rather than at the inside end.

That's why I was recommending Sunrace M9, which like more up-to-date Shimano MTB derailleurs is designed to work with larger sprockets. Unlike more up-to-date Shimano derailleurs, it's designed to work equally well with 5, 6, 7, 8, or 9-speed shifters (but not with 10, 11, or 12, and not with CUES).
Btw can't I just upgrade to shimano 10 speed derailleur that can work with 51T - 47T? Maybe that would give me more spacing by moving 30T to middle position :)
 
Btw can't I just upgrade to shimano 10 speed derailleur that can work with 51T - 47T? Maybe that would give me more spacing by moving 30T to middle position :)
I think any 10sp Shimano MTB derailleur (other than CUES) should work with your shifter and 10sp sprocket spacing. But you can consult a Shimano compatibility chart from the relevant model year to be sure.
 
I have put the extender on the hanger and that didn't fixed the problem as the derailleur is not working properly, doesn't shift to some gears, tried adjusting it but didn't helped. So I removed it and works good but if I want different cogs, which was the plan, I guess I will have to go with the change of shifter, derailleur and cassette, probably 7 speed. But that will wait until the cassette is ready for replacement.
 
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