I have a lot of questions for the boffins. As I live out in the Bush in Mozambique I cannot gleam information from my LBS or agent and I rely heavily on other users to make my decisions..
I want to do some upgrades to my drive train. My choice is between Shimano XT and SRAM X.9. What tips the scales in the favor of the Shimano derraileurs is that I already have a Shimano Flight Deck that is a very useful tool with a Tandem as it shows you on the screen what gear you are in. Can I fit the Flight deck by using the same wiring as for the current Deore setup or will I have to buy a new mounting bracket and wiring? The SRAM will have to give me a GREAT benefit to swing my choice.
I also want to upgrade to disk brakes. I currently have AVID Arch Rival V-type brakes on the Tandem. They are awesome. Will disks be an upgrade?
My choice is between the Hope M4 disk brakes or the Magura Julie disks. I am new to disks and have had no previous experience with them. Will I be able to fit them myself? I have a 2002 Marzocchi FR series Z1 Wedge Bomber fork on the tandem. Will I need any adaptor to it any of the disks below? I will need longer hoses for the back disk. Can the hoses on the disks below be lengthened? Will I be able to bleed the system myself? Will I be able to fit disk pads myself? The rear dropout of the tandem has standard disk mounts. Anything special here? I have six hole ISO mount DMR Revolver disk hubs front and rear with Sun Mammoth rims on the tandem. Do I need to upgrade to a 20mm axle or will the normal quick release axle work????
I there anything regarding disks I left out or forgot to mention. Remember what I do not know I do not know!!!!!!!!
Derraileurs:
Shimano XT R-Mech M751 GS Long Cage
Shimano XT F-Mech Conventional M761 34.9 Dual TP/BP (48 tooth/63-66 Deg)
Shimano XT Shifter Pod 9sp M751 RH Rear and LH Front Black
OR
SRAM X.9 Rear Mech 9sp Long Cage
SRAM X Generation 9sp F-Mech 31.8/34.9 Dual TP-BP Black
SRAM X.9 Trigger 9sp F&R Pair
Disk Brakes:
Hope Mono M4 Disc Brake Front and Rear with 200 mm rotor front and 180mm rotor
Back.
OR
Magura Julie 2006 Front and rear with 180mm IS Mount, I will order the front hub with a 210mm rotor and back with a 180mm rotor.
Thanx in advance
Big H
stapfam
02-16-06, 12:39 PM
Hi
My choice is between the Hope M4 disk brakes or the Magura Julie disks. I am new to disks and have had no previous experience with them. Will I be able to fit them myself? I have a 2002 Marzocchi FR series Z1 Wedge Bomber fork on the tandem. Will I need any adaptor to it any of the disks below? I will need longer hoses for the back disk. Can the hoses on the disks below be lengthened? Will I be able to bleed the system myself? Will I be able to fit disk pads myself? The rear dropout of the tandem has standard disk mounts. Anything special here? I have six hole ISO mount DMR Revolver disk hubs front and rear with Sun Mammoth rims on the tandem. Do I need to upgrade to a 20mm axle or will the normal quick release axle work????
I there anything regarding disks I left out or forgot to mention. Remember what I do not know I do not know!!!!!!!!
Big H
I run a mix of XT and XTR on my Dale MT. My upgrade was from LX and the XT is worth it, but only upgrade when worn out as the LX is still pretty good. XTR is pricey but better, but worth the extra?
I had some form of Avid V brakes on mine when I got it and they were good but the change to Hope Mono M4's was well worth the expense. 200mm disc up front and 180 rear sounds good- I have 200mm F & R and have just a bit too much rear brake. I would definitely go with the 20mm axle though. The variety of calipers made by Hope to fit the Different Disc sizes to various Forks and frames is tremendous so a bit of research may be necessary to find which "Size" caliper to fit may be necessary. I initially ran the 2002 Marzochhi Freeride dropoffs with the 200mm disc and it took a no4 caliper. When I changed to the Rockshox Boxers- it took a different caliper- See the problem? With a 180mm disc on the rear- A standard no4 caliper will fit- but to accomodate the 200mm disc- I had to get a Mounting to extend the caliper away from the Hub- While on hubs- You may need a spacer to push the disc outboard- which I think is 5mm.- to accomodate the 145mm axle as opposed to the 135 of most solos. While on spacers- My Dale came woth non standard IS mounts and I made up a spacer to replace the disc spacer and the extra distance required. May seem crude but it works, has not been detrimental to the brakes and has been on for 4 years. (See Attachment)
The system comes fully bled but you will have to change the rear piping, and probably cut the front to length. Sharp stanley knife will cut easily- but does take a bit of pressure to pull the old piping off the connector. A straight pull with a pair pliers worked for me but it does take a strong- straight pull. Hope Do a tool for bleeding the brakes and I have heard that it works very well. I dont have the tool and bleeding for me takes 4 hands and a tight fitting bleed pipe. By the way- use DOT 5.1 brake fluid.
Fitting is no problem- unless you are not mechanically minded. Spacing of the caliper centrally over the disc is the only bit to worry about and this is done seemingly crudely by washers. Hope call them spacers, but a good supply of various thicknesses is supplied- Took me 3 attempts to centalise the caliper and no adjustments have since been necessary.- I have redone the front once- but finished up with exactly the same washers.
Two points- Before you start- get some loctite- Screw lock, thread fix or whatever it is called where you are. And secondly- I use the syntered pads. They are harder and do not not fade when hot- May wear the disc out quicker, but no wear on my discs after 5,000 miles, and they may squeal- not that I have noticed that. There is a normal organic pad but I have never used them- but they are supposed to be better in wet conditions or in the cold. If they Give more daylight under the back wheel than I get with Syntered, then I don't want them.
Edit- Trouble with working from memory- it does not work. The caliper no I used is not a no4-- It is a no8
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atbhaack
02-17-06, 07:46 AM
Hello,
Most disc brake companies do not recommend using anything larger then a 160 rotor with a quick release. They fear that the power generated by the larger brakes can snap a QR.
I thought long and hard when I built up mine. I went with a full xt drive train. But sram has an advantage that it pulls and releases twice the cable per shift. This will let the derailors stay in tune longer. Although the xt on my tandem seems to shift better then any of my other bikes.
I found that the rear disc does need a longer hose. I also found that jagwire makes the least expensive hydrolic tubing in bulk. It also looks just like the hopes. I would not be surprised if hope uses this housing.
Peak Team
02-18-06, 02:38 AM
Have a Hope Mono M4 on the rear of our road/trail tandem. Works very well and is now our primary brake (have V brakes too).
Hope can supply the brakes with extended lenght hoses for rear tandem use. I have the stainless steel braided hose which came at a nominal extra cost on a new brake.
I agree with the comments below that getting the right mounting is a trick. Our tandem has a front mounting fitted on the rear to give the correct spacing - so really looks like a try and see if it fits job.
Can't comment on the need for 20 mm axles - would certainly be stronger and have a reduced risk of pull out.
I recall from some friends who have travelled internatonally that bleeding may be required when hydraulic brakes have been moved by air. Not supposed to be a hassle with Hope brakes, but I haven't had to do it yet. Replacing the brake pads takes a few minutes.
Good luck !
Jyves
02-18-06, 04:06 AM
Sorry for my english
For me SRAM is a better choise. Ratio for rear is 1:1. The filling is more hard than shimano but that's working better. On our tandem, Sram x7 and twiwter x7. For our futur tandem, Sram x9 and X0 twister. I prefere the simplicity of twister, shifters are more techniqual. But if you can open and repair the Sram shifters, it is vey difficult with Shimano shifter.
Jyves
http://enfinletandem.blogspot.com/
Big H
02-22-06, 03:42 AM
Thanx for all the help.
Stapfam
I will have to go for Avid Juicy 7's. We do not have an agency for Hope disks in South Africia (my closest "civilised" country)
Also I am unclear as to what the mode of failure can be with a normal hollow Cromoly axle with a stressed skewer. Structurally this is a very sound union. Somebody mentioned the skewer might snap. The purpose of the skewer is surely only to keep the wheel in place. What extraneous forces are present???. The secondary purpose of the skewer is to act as a structural stiffener of the hollow axle thus further enhancing its soundness.
Has the failure of skewered axles with rotors large than 160-180mm been encountered before?? and documented explaining the cause or is this the manufacturers safeguarding themselves in a law suit crazy society???.
Big H
Big H
02-27-06, 08:17 AM
Thanx for all the help.
Stapfam
I will have to go for Avid Juicy 7's. We do not have an agency for Hope disks in South Africia (my closest "civilised" country)
Also I am unclear as to what the mode of failure can be with a normal hollow Cromoly axle with a stressed skewer. Structurally this is a very sound union. Somebody mentioned the skewer might snap. The purpose of the skewer is surely only to keep the wheel in place. What extraneous forces are present???. The secondary purpose of the skewer is to act as a structural stiffener of the hollow axle thus further enhancing its soundness.
Has the failure of skewered axles with rotors large than 160-180mm been encountered before?? and documented explaining the cause or is this the manufacturers safeguarding themselves in a law suit crazy society???.
Big H
Big H
02-27-06, 08:22 AM
Thanx for all the help.
Stapfam
I will have to go for Avid Juicy 7's. We do not have an agency for Hope disks in South Africia (my closest "civilised" country)
Also I am unclear as to what the mode of failure can be with a normal hollow Cromoly axle with a stressed skewer. Structurally this is a very sound union. Somebody mentioned the skewer might snap. The purpose of the skewer is surely only to keep the wheel in place. What extraneous forces are present???. The secondary purpose of the skewer is to act as a structural stiffener of the hollow axle thus further enhancing its soundness.
Has the failure of skewered axles with rotors large than 160-180mm been encountered before?? and documented explaining the cause or is this the manufacturers safeguarding themselves in a law suit crazy society???.