# can i use 9/10 speed rear derailleur on 8 speed casstte?



## akacoke (May 11, 2011)

hi, im new to bikes, my bike is 8 speed. can i use a 9 or 10 speed rear derailleur on my 8 speed cassette?

if it would work how to adjust it?

thanks

my bike has Shimano Deore rear derailleur and Altus EF51 now, im looking at the sram x line. some of the ad showing sram would require esp shifter, what does this mean? if they are not compitable, whats good upgrade from my current parts?


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## David C (May 25, 2011)

Hi,

You can use any 9 speed rear derailleur with a 9-8-7-or smaller cassette. You will need a 10 spd rear derailleur to work with a 10 spd cassette, because the spacing is smaller with a 10 spd setup.

You will need a 10 speed chain for a 10 speed setup, a 9 speed chain for a 9 speed setup and any 8 speed chain will work on 8-7-6 speed or lower.

Since they don't pretty make 8 speed drive train much, they just do 9 spd der or 10 spd der.

Just a tip, when posting a question like that, just try to name the brand, year and model of the bike you have...

And yes, a shimano der will work with any cassette and a SRAM der also.

You will have to buy the derailleur depending on your shifters, since SRAM derailleur are only compatible with SRAM shifters and Shimano derailleur are only compatible with Shimano shifters.

Then you all good to go.

David

ps : der = derailleur


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## AndrwSwitch (Nov 8, 2007)

Shimano and SRAM have both broken reverse-compatibility with their 10-speed drivetrains.

You can use a 9-speed derailleur. You CAN NOT use a 10-speed.

Your Deore rear derailleur is already a pretty nice part. Use it until it wears out or you break it.

In general, the brand of the shifters and rear derailleur needs to match. The number of speeds of the shifters, cassette and chain needs to match.

The Deore front derailleur and shifters are pretty nice.

Bikes that come with this stuff on them are a giant money pit when you start trying to upgrade them. So as long as things are actually working, try to be disciplined about it, and think about what bike would really fit the kind of riding you love the most.


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## David C (May 25, 2011)

akacoke said:


> hi, im new to bikes, my bike is 8 speed. can i use a 9 or 10 speed rear derailleur on my 8 speed cassette?
> 
> if it would work how to adjust it?
> 
> ...


This is why I always think its a good idea to quote the text you are answering in your post, as if I did first, you would see that that info in red wasn't there at the time...

Now yes, like Andre said, you need a Shimano der to fit with your Shimano shifters... and for trail and light All mountain, Deore is really nice, light, durable and also cheap compare to XT price...

Unless you can't avoid it, upgrading from Shimano to SRAM will cost you a bit, like the Deore is little up the X-5 and Deore LX is about X-7... But the value of X-7 over X-5 is lot better and if you ever go for the whole upgrade, then go to the X-9 shifters, X-7 rer der and X-7/X-9 front der depending on your budget... Or you might have even moar money and go for the lifetime investment that the X0 series is... I prefer the performance of SRAM over Shimano, but Shimano stuff is more durable, since they have pretty much the same line up since years, so not anything really fancy with them, high price and durability... SRAM is a bit cheaper, but you really feel that you get more for your money the Shimano do.

Just look at price and see if you really need to upgrade... Is it more of a caprice or a need ?

David


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## akacoke (May 11, 2011)

i think im gonna just keep the deore. i thought there would be a lot of rust, because the front der is covered by rust, turns out the rear der is just fine.


i gusse i will spend the money on a nice fork. right now the crome tubes have some deep scratches, where the scratches at kinda rusted. although it doesnt leak. im not sure i could still use it or not. the bike is a specialized p2 2004, the fork is a bomber 100mm travel

also the cassette is 40% covered by rust, but no rust where the teeth at. i dont know if i should replace it , its a Shimano HG-50, 8 speed. im looking at sram pg850, its 17.98 shipped from amazon.


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## David C (May 25, 2011)

akacoke said:


> i think im gonna just keep the deore. i thought there would be a lot of rust, because the front der is covered by rust, turns out the rear der is just fine.
> 
> i gusse i will spend the money on a nice fork. right now the crome tubes have some deep scratches, where the scratches at kinda rusted. although it doesnt leak. im not sure i could still use it or not. the bike is a specialized p2 2004, the fork is a bomber 100mm travel
> 
> also the cassette is 40% covered by rust, but no rust where the teeth at. i dont know if i should replace it , its a Shimano HG-50, 8 speed. im looking at sram pg850, its 17.98 shipped from amazon.


I got my HG-50 for $2.34 on eBay, new, plus $7 shipping... And I like it pretty much, since a full summer at the beach, no rust at all. But try to degrease the whole thing...

Look in the beginners corner, I've gave a dude a complete procedure to make everything nice again and after typing it 3 times in a row today, I don't want to type it again on my iPhone a fourth time now... Threads called : "tips to degrease clean a cassette/drivetrain" I think or something similar.

David


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## akacoke (May 11, 2011)

David C said:


> I got my HG-50 for $2.34 on eBay, new, plus $7 shipping... And I like it pretty much, since a full summer at the beach, no rust at all. But try to degrease the whole thing...
> 
> Look in the beginners corner, I've gave a dude a complete procedure to make everything nice again and after typing it 3 times in a row today, I don't want to type it again on my iPhone a fourth time now... Threads called : "tips to degrease clean a cassette/drivetrain" I think or something similar.
> 
> David


i just read your post, my bike is not as dirty , i wonder if i can use the TSP to clean off rust?

when i got the bike, it had been sitting outside for yrs, its got some wheather damage to it, im getting some bb7s, new brake housing and cable, just got new wheels. last thing would be fork. right now there are nothing like what you paid for similar cassetts on ebay

here are some pics


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## David C (May 25, 2011)

akacoke said:


> i just read your post, my bike is not as dirty , i wonder if i can use the TSP to clean off rust?
> 
> when i got the bike, it had been sitting outside for yrs, its got some wheather damage to it, im getting some bb7s, new brake housing and cable, just got new wheels. last thing would be fork. right now there are nothing like what you paid for similar cassetts on ebay
> 
> here are some pics


Yep, TSP will remove rust too, and will not damage the paint or finish.

Just rinse it off then, wipe it dry and it can get almost like new.

The cassette I bought was with the bidding, but your there look very nice still. Remove it, disassembled it and clean it and it will be like new.

For the fork, if there is rusted scratches, you might simply want a new one, since it probably not worth it trying to fix this one.

David


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## gmcttr (Oct 7, 2006)

The rust on the cassette and chainrings is only cosmetic and won't hurt performance at all, so no need to replace them.

The rust on the forks will wear on the seals and shorten their life. I would use very fine steel wool or maybe a scotchbrite pad to clean it up a little. The idea is to smooth out the rust, not scratch up the stanchions.


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## akacoke (May 11, 2011)

sounds great, thanks for the input. 

im looking at a Marzocchi Drop Off 4/sl on CL, i will probabely go pick it up in a couple of hrs.

is this fork ok? is it oil or air? i searched for long time, info was confusing. 

also, where is a good place to buy TSP?


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## David C (May 25, 2011)

akacoke said:


> sounds great, thanks for the input.
> 
> im looking at a Marzocchi Drop Off 4/sl on CL, i will probabely go pick it up in a couple of hrs.
> 
> ...


Any auto parts have the TSP.

For the fork, if the condition's good, it's a good buy. And it's air.

David


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## akacoke (May 11, 2011)

David C said:


> Any auto parts have the TSP.
> 
> For the fork, if the condition's good, it's a good buy. And it's air.
> 
> David


i didnt buy it, there are few deep scratches on the upper tube, the bottom part is a bit beat up too.

i spend some time tried to sand the upper tubes of my bomber fork, it helped a lil bit, but still not much. all the decent forks are too expensive, a cheap one like suntour xct that i used to have sucks. used ones are either beat up or pricey. im kinda lost here


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## hardwarz (Jun 12, 2009)

Wait a minute... Something doesn't seem right... The distance between the small and large cog on a 8 speed - 10 speed cassette is the same, only the spacing is different. The rear derailleur doesn't have any stops built in. It just goes the same distance that the shifter pulls on the cable, therefore, why couldn't you use a rear derailleur from an 8-9 speed on a 10 speed as long as you use a 10 speed shifter.

I understand using a 10 speed cassette and chain, but the 10 speed cassette works on a 8/9 speed hub, there for they adjusted spacing between the cogs in the cassette. Therefore any 8/9/10 rear derailleur SHOULD be able to get from the small cog to the large cog and the shifter will make the length of pull adjustments.

Something is fishy here...


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## Ken in KC (Jan 12, 2004)

*Some advice...*



David C said:


> This is why I always think its a good idea to quote the text you are answering in your post, as if I did first, you would see that that info in red wasn't there at the time...
> 
> Now yes, like Andre said, you need a Shimano der to fit with your Shimano shifters... and for trail and light All mountain, Deore is really nice, light, durable and also cheap compare to XT price...
> 
> ...


David,

When dispensing advice on the Beginner's Forum, we generally try to avoid offering opinions as facts.

To the OP: I know you've decided to keep your current drive train. Chances are the rust can be removed with a little oil and elbow grease. Generally, drive train performance and durability is about the same. The difference in price corresponds with a reduction in weight.

SRAM vs Shimano is a personal preference.


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## David C (May 25, 2011)

Ken in KC said:


> SRAM vs Shimano is a personal preference.


Yep.


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## blunderbuss (Jan 11, 2004)

hardwarz said:


> Wait a minute... Something doesn't seem right... The distance between the small and large cog on a 8 speed - 10 speed cassette is the same, only the spacing is different. The rear derailleur doesn't have any stops built in. It just goes the same distance that the shifter pulls on the cable, therefore, why couldn't you use a rear derailleur from an 8-9 speed on a 10 speed as long as you use a 10 speed shifter.
> 
> I understand using a 10 speed cassette and chain, but the 10 speed cassette works on a 8/9 speed hub, there for they adjusted spacing between the cogs in the cassette. Therefore any 8/9/10 rear derailleur SHOULD be able to get from the small cog to the large cog and the shifter will make the length of pull adjustments.
> 
> Something is fishy here...


Shimano and SRAM's 10 speed MTB shifters have a slightly different cable pull ratio than their 8/9 speed stuff, and the derailleurs are designed accordingly.


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## David C (May 25, 2011)

blunderbuss said:


> Shimano and SRAM's 10 speed MTB shifters have a slightly different cable pull ratio than their 8/9 speed stuff, and the derailleurs are designed accordingly.


Yep, that's fishy. They did that only to sell more der, since people would have used their 9 spd one as 10 spd...

Kinda SRAM and Shimano compatibility...

David


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## matt4x4 (Dec 21, 2013)

Hey, sure this is an old post. 2011. I came across this in my google search and decided to register and post here.

So besides the bad english typed here by a few, its a little confusing as to what you are trying to say. Plus there is conflicting info between 2 different posters.

My issue(s).......

I got SRAM components on my used 2009 Specialized mountain bike, that I just bought 
(8 speed components), with no rear derailleaur, no hangar ($20 from bike store). Now the 26" wheels on this bike are not stock, because I check out the Suppoer/Archives of Specialized website, so the wheels on this bike now have a 9 speed cassette (which should be a stock 8 speed cassette), which when the chain is on the smallest rear cog, there is evidence that the previous owner had the chain hit the frame, which in turn would probably lock the chain between the cassette to the frame. Which proves that 9 speed cassette doesnt belong on this bike. Plus I dont like the shifters on this bike SRAM X-4, 8-speed, you use your thumb for both triggers, and to use one of the triggers you have to awkwardly shove your thumb at an un-natural angle to shift. The small/short trigger. So with that, and no rear deraillear or hangar, I am swapping parts from one bike to another. Both Shifters, Both derailleaurs.

My other 2007 Specialized crosstrail "Parts" bike has all Shimano components. 
Yes I know no cross-compatibility SRAM-Shimano. Because of the ratios (2:1 and 1:1)
Brake levers are both the same, rotors are both the same.


So Shimano M-581 Deore LX long cage rear derailleur (9 speed), 
Shifters are Shimano SL-511 Deore, 9-speed Rapid Fire (Thumb/Index Finger which I love)

If I leave the 9 speed cassette in, saving me $20 bucks (slang), couldnt I just stop the derailleaur from going to the smallest cog by those little adjuster stop screws. The cassette itself doesnt rub the frame, which is good news.

If I go with the 8 speed cassette route, this will probably now become a hassle right?


I just absolutely hate it when the chain gets stuck between the spokes/cassette and the frame/cassette. 

I will thank you in advance for the advice given me, and I will wish everyone a Merry Christmas and a Happy New Year.

Cheers


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## hardwarz (Jun 12, 2009)

*This is an old thread!!!*



matt4x4 said:


> My issue(s).......
> 
> I got SRAM components on my used 2009 Specialized mountain bike, that I just bought
> (8 speed components), with no rear derailleaur, no hangar ($20 from bike store). Now the 26" wheels on this bike are not stock, because I check out the Suppoer/Archives of Specialized website, so the wheels on this bike now have a 9 speed cassette (which should be a stock 8 speed cassette), which when the chain is on the smallest rear cog, there is evidence that the previous owner had the chain hit the frame, which in turn would probably lock the chain between the cassette to the frame. Which proves that 9 speed cassette doesnt belong on this bike. Plus I dont like the shifters on this bike SRAM X-4, 8-speed, you use your thumb for both triggers, and to use one of the triggers you have to awkwardly shove your thumb at an un-natural angle to shift. The small/short trigger. So with that, and no rear deraillear or hangar, I am swapping parts from one bike to another. Both Shifters, Both derailleaurs.


The SRAM shifters are great because you have have more control on the grip, especially if you're index finger is on the brakes. If you have to reach at a weird angle, rotate the shifter. The shifter lever that is further back should be perpendicular to the ground. Depending, you may need to even bring it so the back trigger is slightly forward in rotation.

If the chain got logged between the frame an the smallest cog, it tells me that the person before you did not set the limits correctly.



matt4x4 said:


> If I leave the 9 speed cassette in, saving me $20 bucks (slang), couldnt I just stop the derailleaur from going to the smallest cog by those little adjuster stop screws. The cassette itself doesnt rub the frame, which is good news.


I assume that you have a 3x9 drivetrain. I assume this because you have a long cage. Set the limits correctly and run the full 3x9.



matt4x4 said:


> If I go with the 8 speed cassette route, this will probably now become a hassle right?


The spacing on the rear hub is the same for 8 or 9. You can interchange them. The issue is that the gears are closer between 8 and 9 speeds. 9 speed chains are narrower than 8 speed chains. 6/7/8 speed chains are interchangeable. If you were to go to a 8 speed cassette, you'd have to change your rear cassette, rear shifter and rear derailleur all to 8 speed.



matt4x4 said:


> I just absolutely hate it when the chain gets stuck between the spokes/cassette and the frame/cassette.


If the chain is getting stuck, your High and Low limits aren't set correctly. On the rear derailleur, the H should be the smallest cog and the L the largest cog.

Here's a link if you decided you want to do more reading on the subject.

Merry Christmas and a Happy New Year.


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## AndrwSwitch (Nov 8, 2007)

matt4x4 said:


> Hey, sure this is an old post. 2011. I came across this in my google search and decided to register and post here.
> 
> So besides the bad english typed here by a few, its a little confusing as to what you are trying to say. Plus there is conflicting info between 2 different posters.
> 
> My issue(s).......


Okay, I couldn't follow the rest of your post.

What's on your bike now?

What was the question?


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## matt4x4 (Dec 21, 2013)

> Okay, I couldn't follow the rest of your post.
> 
> What's on your bike now?
> 
> What was the question?


Hahaha, yeah.
The questions were answered, but found a few more issues and got a few more Q's.

The Bikes are

This is the bike I want to ride.
Primarly all SRAM some Shimano on the 2009 Specialized Rockhopper has a FRONT DERAILLEUR Shimano Altus, 34.9mm clamp, top swing. REAR DERAILLEUR SRAM X-5, med. cage
SHIFT LEVERS SRAM X-4, 8-speed trigger
CASSETTE SRAM PG-830-I8, 8-speed, 11-32t
CHAIN KMC X8 w/ reuseable Missing Link
CHAINRINGS 42S x 32S x 22S

This bike I dont care about.
All Shimano on the 2007 Specialized Crosstrail Expert has a FRONT DERAILLEUR Shimano M-530 Deore, 31.8mm clamp, top swing, bottom pull. 3x9.
REAR DERAILLEUR Shimano M-581 Deore LX, long cage, standard spring.
SHIFT LEVERS Shimano SL-511 Deore, 9-speed 
CASSETTE / FREEWHEEL Shimano HG50, 9-speed, 11/32t
CHAIN Shimano HG73, 9-speed
CHAINRINGS 48Ax36Ax26A w/chainguard



> [ If you have to reach at a weird angle, rotate the shifter. The shifter lever that is further back should be perpendicular to the ground. Depending, you may need to even bring it so the back trigger is slightly forward in rotation.
> /QUOTE]
> 
> I tried rotating it, it does seem to work the way you suggested, its still awkward. I just don't like the feel of the SRAM X4 shifters.
> ...


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## sbarnhart (Jun 8, 2011)

Sram makes at least 3 shifters for shimano : Attack, rocket, and Centera I believe. The last is for a comfort bike. There might be one more I am forgetting. To the OP. You will need A SRAM shifter for X3,X5,X7,X9,XO. You will need a 10spd shifter for X1


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## AndrwSwitch (Nov 8, 2007)

You have to buy the derailleur hanger that matches your specific frame. There's no standards, and you cannot make any assumptions about cross-compatibility. In general, I'd expect two frames from different classes to have different hangers.

Your Specialized dealer is pretty likely to have one in stock. Failing that, check out derailleurhanger.com.

Which bike had the interference problem with the rear derailleur?


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## slapheadmofo (Jun 9, 2006)

hardwarz said:


> If you were to go to a 8 speed cassette, you'd have to change your rear cassette, rear shifter and rear derailleur all to 8 speed.


You do NOT have to change derailleurs to go between 7/8/9 speeds.


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## matt4x4 (Dec 21, 2013)

I got the bike all swapped over and its working very nicely. Just have to shorten the chain from 56" to 53" from the Parktool website "Chain Sizing by Equation". Very cool website. 

I was over-reacting to the damage on the frame, thinking I had to spend $100 or more to get it ridable (thats what too many Canadian Beers does to a man......EH!!.) I only spent $25 (hanger and all new cables)

Basically I went from a stock 8 speed Rockhopper hardtail to a 9 speed, with everything matching in terms of speed, it runs smooth and everything is inline. Now the Specialized Crosstrail is stripped. 

Love the 26x2.1 tires on the Rockhopper, they are soooo wide, and they run so straight when hands are off the handlebars. Im not used to it with the previous narrow road tires 700cx38's I had. 

Now its time to electrify my sweet beautiful bike to about 2000 watts, direct drive hub motor, 60V 15Ah RC Lipo batteries and a 30A controller. should get me going quite fast. Its going to cost me a few "Sir Robert Laird Borden's=$100CDN aka Benjamin Franklins USD"
ok ok I will lay off the Egg Nog and rum for a little while.


Thanks for the help.


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