Shimano Deerhead RD question
#1
Aspiring curmudgeon
Thread Starter
Join Date: Aug 2014
Location: Saint Louis
Posts: 2,486
Bikes: Guerciotti, Serotta, Gaulzetti
Likes: 0
Liked 26 Times
in
13 Posts
Shimano Deerhead RD question
Does anyone know the smallest cog a Shimano Deerhead RD (1st gen Deore XT) can handle? According to disraeli gears, the max cog is 34t, and my current freewheel's smallest cog is 14t, but I'd like to run it on an 8 speed cassette with an 11t if possible. Mine is the superplate version, if that matters.
__________________
"Party on comrades" -- Lenin, probably
"Party on comrades" -- Lenin, probably
#2
Bianchi Goddess
Join Date: Apr 2009
Location: Shady Pines Retirement Fort Wayne, In
Posts: 28,131
Bikes: Too many to list here check my signature.
Liked 3,267 Times
in
1,649 Posts
You may have to experiment. What is the max wrap for that derailleur? If your still trying to run the 34 but drop to a 11 with a wide Alpine type triple you may be maxing out the derailleur.
__________________
“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk
“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk
#3
Aspiring curmudgeon
Thread Starter
Join Date: Aug 2014
Location: Saint Louis
Posts: 2,486
Bikes: Guerciotti, Serotta, Gaulzetti
Likes: 0
Liked 26 Times
in
13 Posts
The max wrap according to disraeli is 40t. It's set up in a very wide TA triple now (Half-step plus granny, I think its 52-48-28ish). But I'm moving it to another frame to set up as a 44t single.
__________________
"Party on comrades" -- Lenin, probably
"Party on comrades" -- Lenin, probably
#4
Senior Member
Join Date: Nov 2011
Location: Port Angeles, WA
Posts: 7,927
Bikes: A green one, "Ragleigh," or something.
Liked 644 Times
in
361 Posts
The manufacturers usually understate their RDs actual capacity by a significant margin. As a fairly inexperienced mechanic, I've never really considered "how small can you go" as question needing asking, only "how large."
FWIW, the Deore DX I have that's a couple generations after Deerhead works just fine on a 7-speed cassette I have that's 12-32. I bet it would go down to 11, but I don't have one to try, so I can't test that.
FWIW, the Deore DX I have that's a couple generations after Deerhead works just fine on a 7-speed cassette I have that's 12-32. I bet it would go down to 11, but I don't have one to try, so I can't test that.
__________________
● 1971 Grandis SL ● 1972 Lambert Grand Prix frankenbike ● 1972 Raleigh Super Course fixie ● 1973 Nishiki Semi-Pro ● 1979 Motobecane Grand Jubile ●1980 Apollo "Legnano" ● 1984 Peugeot Vagabond ● 1985 Shogun Prairie Breaker ● 1986 Merckx Super Corsa ● 1987 Schwinn Tempo ● 1988 Schwinn Voyageur ● 1989 Bottechia Team ADR replica ● 1990 Cannondale ST600 ● 1993 Technium RT600 ● 1996 Kona Lava Dome ●
● 1971 Grandis SL ● 1972 Lambert Grand Prix frankenbike ● 1972 Raleigh Super Course fixie ● 1973 Nishiki Semi-Pro ● 1979 Motobecane Grand Jubile ●1980 Apollo "Legnano" ● 1984 Peugeot Vagabond ● 1985 Shogun Prairie Breaker ● 1986 Merckx Super Corsa ● 1987 Schwinn Tempo ● 1988 Schwinn Voyageur ● 1989 Bottechia Team ADR replica ● 1990 Cannondale ST600 ● 1993 Technium RT600 ● 1996 Kona Lava Dome ●
#5
Extraordinary Magnitude
Join Date: Aug 2009
Location: Waukesha WI
Posts: 13,765
Bikes: 1978 Trek TX700; 1978/79 Trek 736; 1984 Specialized Stumpjumper Sport; 1984 Schwinn Voyageur SP; 1985 Trek 620; 1985 Trek 720; 1986 Trek 400 Elance; 1987 Schwinn High Sierra; 1990 Miyata 1000LT
Liked 1,791 Times
in
988 Posts
I guess the way I think about it is that the big cog is the limiting factor- the upper jockey has to be beneath the respective cogs. The distance is one of the primary factors to determine how well it shifts.
__________________
*Recipient of the 2006 Time Magazine "Person Of The Year" Award*
Commence to jigglin’ huh?!?!
"But hey, always love to hear from opinionated amateurs." -says some guy to Mr. Marshall.
Commence to jigglin’ huh?!?!
"But hey, always love to hear from opinionated amateurs." -says some guy to Mr. Marshall.
#6
Collector of Useless Info
Deerhead was before Suntour's slant-parallelogram patent ran out, so it won't have optimal shifting on the smaller cogs; it just won't track the cassette that well. But it will work. Hyperglide cogs help.
#7
Really Old Senior Member
I used that RDER & shifters from 12-28 7 speed, through 8 speed to a 12-23 9 speed on my 86 Rockhopper.
Although I had no need for an 11T small cog, I sincerely feel it wouldn't have been a problem.
Shifting actually got better as I added cogs, due to ergonomics of my thumb etc.
I probably hit my gear 95% of the time until I got N+1 with trigger shifters.
My friction shifting skills went down the tube.....
Although I had no need for an 11T small cog, I sincerely feel it wouldn't have been a problem.
Shifting actually got better as I added cogs, due to ergonomics of my thumb etc.
I probably hit my gear 95% of the time until I got N+1 with trigger shifters.
My friction shifting skills went down the tube.....