ENR. Reducing drag.

moorey

moorey

call me Mia
Hey brains trust, throwing this out there to see if my feeble brain is missing anything.
Bike has 50mm or rearward axle path, so the lower chain guide is essential, to free up more chain as you compress suspension.
They came out with eagle 50t, and when in the big cogs…ie climbing…the drag is more noticeable. I only run a 42t these days, which has less drag already, but I reckon I can reduce further if I lower the guide further. When fully compressed, I’m no where near running out of chain using an SGS m8000 derailleur

So…I’m thinking…..the ISCG05 guide that comes on the bike doesn’t have slotted mounts like bought ones, so I can’t rotate the roller a bit lower. I could either file/drill slots in the stock one, or cut the top off spares slotted guides I have.

Stop me any time…
386477
386478
 
Ackland

Ackland

chats d'élevage
Surely someone has an old roller guide in their parts bin

or go bling
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DH GF Guide | eightyonespices

The DH version of the Carbocage chain guide, for 35-38t chain rings and with a durable bash guard. The Carbocage DH is designed for frames of medium to long travel. Carbocage chain guides are now also available in an inexpensive glass fiber construction. It has the same features as the carbon...
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leitch

leitch

Feelin' a bit rrranty
I'd test fit that LG1 (which has the most adjustability between the longest ISCG bolt holes and the adjustable lower roller position) with the top guide removed and see how little lower roller tension you can get away with.

Also, how essential is the guide actually? Have you taken it off and test cycled the suspension in different gears? Hypothetically you're likely to be in higher gears (with more available chain) when you're blowing through travel and hence instigating more growth... Maybe there's a sweet spot where you can get away without it as long as you don't bottom out in 36-46t (for example) which is unlikely to happen anyway? Ah, re-read and saw 42t. Probably not a huge difference then.
 
moorey

moorey

call me Mia
leitch said:
I'd test fit that LG1 (which has the most adjustability between the longest ISCG bolt holes and the adjustable lower roller position) with the top guide removed and see how little lower roller tension you can get away with.

Also, how essential is the guide actually? Have you taken it off and test cycled the suspension in different gears? Hypothetically you're likely to be in higher gears (with more available chain) when you're blowing through travel and hence instigating more growth... Maybe there's a sweet spot where you can get away without it as long as you don't bottom out in 36-46t (for example) which is unlikely to happen anyway? Ah, re-read and saw 42t. Probably not a huge difference then.
Click to expand...
Guide is critical. You’d need a derailleur with an XL cage otherwise.
Probably right about testing with the top removed before cutting.
 
moorey

moorey

call me Mia
Mattyp said:
Does the lower chain guide have a wheel? Or is it just sliding across a guide?
Click to expand...
Wheel. It’s similar drag to a DH bike…except you’re not trying to pedal a DH bike for hours.
Honestly, it’s not bad, I’d just like to try to reduce. Because reasons.
 
leitch

leitch

Feelin' a bit rrranty
moorey said:
Guide is critical. You’d need a derailleur with an XL cage otherwise.
Probably right about testing with the top removed before cutting.
Click to expand...
Tried running the bike with the derailleur clutch turned off?
 
LPG

LPG

likes thicc birds
Can you test with the guide removed completely to see what sort of improvements you could get at best case scenario? I'm thinking a controlled test like an empty uphill road or driveway. You don't want to stuff around trying to make improvements that aren't really there.

Also, when you say you run 42t, is that a 1x-42 cassette or similar or do you not use the bottom gear? If it is you not using the bottom gear the drag could be chain line related
 
moorey

moorey

call me Mia
leitch said:
Tried running the bike with the derailleur clutch turned off?
Click to expand...
Yep. Bit less drag, but unacceptable chain bounce. I’ve only ever lost a chain once. Was with a run I had it turned off accidentally. Could be coincidence of course.
 
moorey

moorey

call me Mia
LPG said:
Can you test with the guide removed completely to see what sort of improvements you could get at best case scenario? I'm thinking a controlled test like an empty uphill road or driveway. You don't want to stuff around trying to make improvements that aren't really there.

Also, when you say you run 42t, is that a 1x-42 cassette or similar or do you not use the bottom gear? If it is you not using the bottom gear the drag could be chain line related
Click to expand...
True. I could just remove the lower to test best case scenario. Good thinking.
9-42 cassette. Chain line doesn’t help. The higher the guide pulls it up, the worse it runs through the lower derailleur jockey. It chews them out pretty fast it seems.
 
dazz

dazz

Downhill Dazz
Few thoughts from the fancy pants step drill guy:

Initial thought is to improve the tiny idler setup to something that has a bit more refinement and development towards minimising drag.
How many good condition low drag larger dia derailleur idlers you got laying around ya spares? The bigger cog will have a much smoother chain line, and will spin more slowly than the tiny idler which should lower the drag from the bearing seals.
Ground clearance doesn't look to be a prob here, so if you can Frankenstein it all together with the brackets and covers/guides you've got there, might deliver the desired result. 3D printing some custom parts could be an option if modification is gonna have that not quite right look.

Happy to help out with some CAD if ya like, would be a fun little project.
 
cokeonspecialtwodollars

cokeonspecialtwodollars

Fartes of Portingale
dazz said:
Few thoughts from the fancy pants step drill guy:

Initial thought is to improve the tiny idler setup to something that has a bit more refinement and development towards minimising drag.
How many good condition low drag larger dia derailleur idlers you got laying around ya spares? The bigger cog will have a much smoother chain line, and will spin more slowly than the tiny idler which should lower the drag from the bearing seals.
Ground clearance doesn't look to be a prob here, so if you can Frankenstein it all together with the brackets and covers/guides you've got there, might deliver the desired result. 3D printing some custom parts could be an option if modification is gonna have that not quite right look.

Happy to help out with some CAD if ya like, would be a fun little project.
Click to expand...
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HOLLOWcage Carbon Ceramic Oversized Derailleur Pulley Cage

Shimano 9100 / 8000. Revolutionary mono-plate design is the quietest, best shifting, aerodynamic derailleur cage design created to date.
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These keep popping up in my feed and now I know why, modify one to suit and I'll bet you end up with negative drag.

EDIT: "Limited stock available. Don't wait, order now." :D
 
Cyclomaniac

Cyclomaniac

Likes Dirt
Those Pinion idlers are horrible. A bit of mud or dust and they become noisy and can jam up where the pin slides through the nylon spacer. One of the reasons I sold the Zerode and kept my ENR.
 
Litenbror

Litenbror

Eats Squid
moorey said:
Not so sure they’d work. Point isn’t to tension, it’s to take up a ton of slack, and release it as suspension compresses and axle moves back 50mm.
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So a chain with a heap of slack is not under....
A chain without any slack would be under....

Yeah there is a reason they went with a skid plate and not jockey wheels. That location would get covered in mud and dust and would be a nightmare to keep going as @Cyclomaniac said. Maybe you could get a jockey wheel setup and just ride on the road?
 
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