Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Mountain Biking Mountain biking is one of the fastest growing sports in the world. Check out this forum to discuss the latest tips, tricks, gear and equipment in the world of mountain biking.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 06-24-11, 08:02 PM   #1
cydewaze
Emondafied
Thread Starter
 
cydewaze's Avatar
 
Join Date: May 2005
Location: Maryland
Bikes: See sig
Posts: 4,858
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
What the heck is Mega9?

I just upgraded my Trek 9700 drivetrain to SLX stuff (RD, crank, chain, shifters), but I didn't bother to get the front derailleur because I already had a 9-sp (E-type) XT front that I bought some time ago.

I'm having a bit of trouble getting the front derailleur adjusted, so I started to wonder if my memory was correct and it really was a 9-sp, so I examined it and found a "Mega9" sticker on the top of the cage.

What the heck is "Mega9" and is it compatible with the rest of my SLX 9-sp stuff?
__________________

my bike page - my journal
Current Stable: Trek Emonda SL - Trek Top Fuel 8 - Scattante XRL - Jamis Dakar Expert - Trek 9700 - AlpineStars Al Mega
cydewaze is offline   Reply With Quote
Old 06-24-11, 08:42 PM   #2
Dannihilator
User Title
 
Dannihilator's Avatar
 
Join Date: Oct 2002
Location: Annandale, New Jersey
Bikes: 2014 Surly Steamroller, 1989 Nishiki Altron
Posts: 19,421
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
It is fully compatible.

Mega 9 was what shimano originally called the 9 speed stuff when it first came out. Just like how dyna-sys is shimano's terminology for 10 speed mtb stuff.

Last edited by Dannihilator; 06-24-11 at 09:00 PM.
Dannihilator is offline   Reply With Quote
Old 06-24-11, 08:57 PM   #3
redtires
Extra Medium Member
 
redtires's Avatar
 
Join Date: Jul 2006
Location: Louisville, Co
Bikes: Arcalis Andorra 01 custom build, Specialized Stumpy
Posts: 1,824
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
^^ yep.
__________________
I like bikes.
redtires is offline   Reply With Quote
Old 06-24-11, 09:17 PM   #4
cydewaze
Emondafied
Thread Starter
 
cydewaze's Avatar
 
Join Date: May 2005
Location: Maryland
Bikes: See sig
Posts: 4,858
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Ah sweet. I guess I just need to get it properly adjusted then. It doesn't seem to want to go into the big ring unless I hold the left thumb shifter, yet it is reluctant to drop to the small ring too. If I tighten the cable, then it rubs in the middle ring when on the big cog out back. I'll fiddle with it more tomorrow.
__________________

my bike page - my journal
Current Stable: Trek Emonda SL - Trek Top Fuel 8 - Scattante XRL - Jamis Dakar Expert - Trek 9700 - AlpineStars Al Mega
cydewaze is offline   Reply With Quote
Old 06-24-11, 09:20 PM   #5
Dannihilator
User Title
 
Dannihilator's Avatar
 
Join Date: Oct 2002
Location: Annandale, New Jersey
Bikes: 2014 Surly Steamroller, 1989 Nishiki Altron
Posts: 19,421
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Limit screws need to be adjusted 1/8 turn at a time.
Dannihilator is offline   Reply With Quote
Old 06-24-11, 09:43 PM   #6
kenhill3
use your best eye
 
kenhill3's Avatar
 
Join Date: Mar 2006
Location: Olympia, Washington
Bikes: '75 Bertin, '93 Parkpre Team 925, '04 Kona King Kikapu, '05 Bianchi Vigorelli
Posts: 3,058
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
+1 on limit screws.

Yup, 'Mega' was Shimano's glossy moniker for 9 speed.

IIRC, there's also an 8speed cassette in Shimano's line up with a 36t called Mega. ?
__________________
"I tell you, We are here on earth to fart around, and don't let anybody tell you any different." - Kurt Vonnegut jr.
kenhill3 is offline   Reply With Quote
Old 06-24-11, 09:46 PM   #7
cydewaze
Emondafied
Thread Starter
 
cydewaze's Avatar
 
Join Date: May 2005
Location: Maryland
Bikes: See sig
Posts: 4,858
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Quote:
Originally Posted by Dannihilator View Post
Limit screws need to be adjusted 1/8 turn at a time.
It's not that. If it were, pushing the thumb lever wouldn't make it shift. The limit screws would stop it dead. Since I can force it into the big ring by holding the thumb lever, it's telling me it wants the cable to be tighter, but if I tighten it, the chain will rub the inside of the FD cage when the RD is in the biggest cog. Not to mention even more of a reluctance to drop to the granny ring.

It's acting like the cage is too wide for the chain, but if it's a 9-sp FD, it shouldn't be. It's almost like the pull ratio is wrong or something, like back with those old Dura-Ace road derailleurs, where depending on which side of the bolt you clamped the cable under, you'd get a different ratio. But I don't think I have any options like that with this FD.
__________________

my bike page - my journal
Current Stable: Trek Emonda SL - Trek Top Fuel 8 - Scattante XRL - Jamis Dakar Expert - Trek 9700 - AlpineStars Al Mega
cydewaze is offline   Reply With Quote
Old 06-24-11, 09:49 PM   #8
scyclops
dont make me get the belt
 
scyclops's Avatar
 
Join Date: May 2010
Location: Southeastern U.S.
Bikes:
Posts: 510
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by kenhill3 View Post
IIRC, there's also an 8speed cassette in Shimano's line up with a 36t called Mega. ?
MegaRange.
scyclops is offline   Reply With Quote
Old 06-25-11, 09:32 AM   #9
cydewaze
Emondafied
Thread Starter
 
cydewaze's Avatar
 
Join Date: May 2005
Location: Maryland
Bikes: See sig
Posts: 4,858
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Quote:
Originally Posted by scyclops View Post
MegaRange.
I've seen those! They're like a huge inner cog on the rear cassette, spaced way away from the others, then there's a big jump to the next gear.
__________________

my bike page - my journal
Current Stable: Trek Emonda SL - Trek Top Fuel 8 - Scattante XRL - Jamis Dakar Expert - Trek 9700 - AlpineStars Al Mega
cydewaze is offline   Reply With Quote
Old 06-25-11, 11:52 AM   #10
cobba
B A N N E D
 
Join Date: Aug 2006
Bikes:
Posts: 1,439
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 23 Post(s)
When tuning the front derailleur you need to have the small front with the large back, middle front with the middle back and the large front with the small back.

Quote:
I can force it into the big ring by holding the thumb lever
This sounds normal.

When fully pushing the thumb lever as far as it can go the derailleur is going past it's indexed position, you can hear a click midway in the push where the indexed position is. You need fully push it past the indexed position so the derailleur can get the chain to go onto the chainring and you need to hold it till it catches on the chainring. When the chain has caught enough to enable it to go around the chainring you release the shifter and the derailleur will go back to it's indexed position.
The outer limit screw needs to be unscrewed enough so this can happen on the outer chainring.

Quote:
the chain will rub the inside of the FD cage when the RD is in the biggest cog
If this is happening when you are using the large front chainring then there isn't a problem, this is a cross chain gear and you shouldn't be using it.

Quote:
it is reluctant to drop to the small ring too
Possibly the deurailleur's pivot links are stiff, try a drop of oil on them.
Is the cable is too tight ?
What gear are you using on the back when doing this ?
If it's the small then that might be the problem. Small front and small back are also cross chaining and gears that shouldn't be used.
As the chain is new it will be much stiffer in it's sideways movement to a old chain and it won't want to go into extreme gear changes like a cross chaining gear, it will want to keep a straight chainline.

Quote:
It's acting like the cage is too wide for the chain
You'd be getting more rub on a narrower cage and you wouldn't be able to use as many gears on the back.
cobba is offline   Reply With Quote
Old 06-25-11, 09:03 PM   #11
cydewaze
Emondafied
Thread Starter
 
cydewaze's Avatar
 
Join Date: May 2005
Location: Maryland
Bikes: See sig
Posts: 4,858
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Quote:
Originally Posted by cobba View Post
When fully pushing the thumb lever as far as it can go the derailleur is going past it's indexed position, you can hear a click midway in the push where the indexed position is. You need fully push it past the indexed position so the derailleur can get the chain to go onto the chainring and you need to hold it till it catches on the chainring. When the chain has caught enough to enable it to go around the chainring you release the shifter and the derailleur will go back to it's indexed position.

The outer limit screw needs to be unscrewed enough so this can happen on the outer chainring.
Going by all that, my current setup is correct other than the chain rub, which as it turns out only actually happens on the stand, so I think I'm ok.


Quote:
Originally Posted by cobba View Post
If this is happening when you are using the large front chainring then there isn't a problem, this is a cross chain gear and you shouldn't be using it.
It was the middle ring/large cog combo.

After a bit of tweaking, I *think* I have it right. The holding the thumb shifter thing is what threw me. I'll know for sure after my first actual of-road ride tomorrow morning.

Thanks for the help!
__________________

my bike page - my journal
Current Stable: Trek Emonda SL - Trek Top Fuel 8 - Scattante XRL - Jamis Dakar Expert - Trek 9700 - AlpineStars Al Mega
cydewaze is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 03:12 AM.