Bicycle Mechanics - 9 spd brifter with 8spd cassette?

So far Uncle Google seems to indicate mostly not possible. Just wondering if folks here would concur.
Am hoping to get by with the 8 cogs rear until time to replace them. Thoughts?

no

If Shimano all you need to be 9-speed is the 9-speed shifters, cassette, and chain (unless your 8-speed is Dura-Ace).
What component group do you have?

It can be done but only if the 8speed cassette is obtained by removing one gear from a 9speed cassette, otherwise no



If Shimano all you need to be 9-speed is the 9-speed shifters, cassette, and chain (unless your 8-speed is Dura-Ace).
What component group do you have?

What happens with 8speed dura-ace? I happen to have 7400 8sp Dura-ace and I am curious..

It can be done but only if the 8speed cassette is obtained by removing one gear from a 9speed cassette, otherwise no




What happens with 8speed dura-ace? I happen to have 7400 8sp Dura-ace and I am curious..

you still need a 8spd dura ace rear

7400 dura ace apparently has a different pull ratio than other shimano rear derailleurs.

To answer the OP, I was able to do the following:
Campy 9 speed ergo, shimano rear, shimano/sram 8 speed cassette.
I was even able to get the ergo to work with shimano 9 speed cassette but that was more finicky.

Have a look at this article. It has pull ratios and spacing for different combinations.
http://www.ctc.org.uk/DesktopDefault.aspx?TabID=3946

Also, you might be able to use a jtek or something like that.

The cassette and chain are far cheaper than the brifters so why not go 9-speed all the way? You don't even have to change your freehub.

but i thought you could use 8 speed sora brifters to convert old school downtube shifting bikes that are 7, 6 or even 5 speed cassettes, you just have 'ghost' shifts?

OK. Sounds like Unc. Google is right. :notamused:

So far Uncle Google seems to indicate mostly not possible. Just wondering if folks here would concur.
Am hoping to get by with the 8 cogs rear until time to replace them. Thoughts?

Jtek sells ratio converters that will do the trick but one will cost as much as a new cassette shipped here from the UK.

but i thought you could use 8 speed sora brifters to convert old school downtube shifting bikes that are 7, 6 or even 5 speed cassettes, you just have 'ghost' shifts?
Not right. All of these are spaced differently and the shifter has to pull the correct amount of cable so the shifter must match the cassette or freewheel. BTW, there were no 5-speed cassettes, only freewheels.

Within modern cog counts, 8 and above, there are adapters from Jtek that will allow a reasonable mis-match of cog spacing and brifters but there is no universal brifter.

what kind of cassette is that 8 speed? I have a 9 speed that I might be willing to trade. It is 11-25 sram. I'll have to check the model number. PM me.

What happens with 8speed dura-ace? I happen to have 7400 8sp Dura-ace and I am curious..

If your 7400 DA are the brifters they will require the DA rear derailluer to shift the 8 spd cassette. BUT, I used the 8 spd DA brifters on a 9 spd cassette for a year without any issues.

Since this thread has already gone well beyond answering the original question, I'll add to the confusion.
It is possible to shift a Shimano 8-speed cassette with a Shimano 9-speed shifter if you use an 8-speed Dura-Ace rear derailleur. As it turns out, the Dura Ace 8-speed shifter cable pull is the same as the cable pull of all Shimano 9-speed shifters. The reason this works is that the 8-speed D-A rear derailleur actuation ratio is different and when combined with a 9-speed shifter the travel for each click matches the 8-speed cog spacing "perfectly".
Take a look at this chart, scroll down to Shimano mech: http://www.ctc.org.uk/DesktopDefault.aspx?TabID=3946

what kind of cassette is that 8 speed? I have a 9 speed that I might be willing to trade. It is 11-25 sram. I'll have to check the model number. PM me.


My 8spd is a HG50 from Shimano.


Al1943

Since this thread has already gone well beyond answering the original question, I'll add to the confusion.
It is possible to shift a Shimano 8-speed cassette with a Shimano 9-speed shifter if you use an 8-speed Dura-Ace rear derailleur. As it turns out, the Dura Ace 8-speed shifter cable pull is the same as the cable pull of all Shimano 9-speed shifters. The reason this works is that the 8-speed D-A rear derailleur actuation ratio is different and when combined with a 9-speed shifter the travel for each click matches the 8-speed cog spacing "perfectly".
Take a look at this chart, scroll down to Shimano mech: http://www.ctc.org.uk/DesktopDefault.aspx?TabID=3946

I have a DA7800. :( yes it worked flawlessly with my 8speed components.
I have an Ultegra FD too. My bike is a smorgasbord of Shimano parts. All I need is to throw in some 105 brakes and it will be a rolling parts bin for Shimano. Maybe get Yumeya Ti-Nitride chain too?

According to this website http://www.ctc.org.uk/DesktopDefault.aspx?TabID=3946
using the Hubbub method it may work. Or am I understanding it incorrectly?

One of the Jtec pulleys fix that?
I stay with a friction shifter scheme, myself, so bypass these issues ..

Sheldon Brown has an example of how to attach the der. cable in this situation. I had exactly the same problem but I could not make this work in my case. You might have better luck. Scroll down to the paragraph near the bottom of the page to "Alternate Cable Routing"

http://www.sheldonbrown.com/derailer-adjustment.html

If your 7400 DA are the brifters they will require the DA rear derailluer to shift the 8 spd cassette. BUT, I used the 8 spd DA brifters on a 9 spd cassette for a year without any issues.
Thanks, I was just curious, I have DA7400 DT shifters (indexed rear, friction front) , DA7400 cassette, DA7400 rear derailleur, in fact it's the whole set (hubs, front mech, headset, cranks, chainring, BB, pedals, calipers, brake levers, brake pads, even the seatpost :D ) - of course not all of them are 7400, but 74xx series like 7400, 7401, 7402, 7403
I have no intend to go to brifters, I just like DT shifters

Sheldon Brown has an example of how to attach the der. cable in this situation. I had exactly the same problem but I could not make this work in my case. You might have better luck. Scroll down to the paragraph near the bottom of the page to "Alternate Cable Routing"

http://www.sheldonbrown.com/derailer-adjustment.html

yep, thats all yo uneed to do I did it with a microshift 9 speed shifter and 8 speed 2200 RD and it worked pretty darn good

there is no universal brifter.

Which sucks. You should be able to buy replacement indexing bits, IMO... I'd like to see someone try it and clean up the competition in the aftermarket scene...

Also, it occurs to me that it should be eminently possible to convert Ergolevers to friction shift.

No can do! (friction in brifter) because the lever has to return after shift not to stay in that position.
The only thing I can picture is a thumb shifter (friction) on the upper part of the hoods of the brifter. That could work.

Thanks, I was just curious, I have DA7400 DT shifters (indexed rear, friction front) , DA7400 cassette, DA7400 rear derailleur, in fact it's the whole set (hubs, front mech, headset, cranks, chainring, BB, pedals, calipers, brake levers, brake pads, even the seatpost :D ) - of course not all of them are 7400, but 74xx series like 7400, 7401, 7402, 7403
I have no intend to go to brifters, I just like DT shifters

^the above is entirely rad
=rob

Two possibilities:
1) If your rear derailer is not Dura-Ace 7400 (or 7401 or 7402), you could try this alternate cable attachment which causes the rear derailer to move about 10% further per shift - http://www.sheldonbrown.com/dura-ace.html#indexing
2) If your rear derailer is Dura-Ace 7400 (or 7401 or 7402), it will already shift 8-speed spacing with Shimano 9-speed shifters.

Just an update..... I applied the "alternate cable routing" method and managed to make it work! 9-spd shifter on a 8-spd cassette using a 10-speed RD!!! How's that for an unholy alliance?!