newredbike

Hi,

I"m sure that this question will have been asked before, but I can't find the answer.

I'm building a Croix de Fer for touring with heavy panniers, I currently have one with a 105 compact drivetrain, which is way to high geared for touring heavily laden ( for me anyway !)

It will have flat bars, which makes the choice of shifters a little difficult.

First question, can a front SL-RS700 shifter which is specified for a 105 system on flat bars be replaced with an M8000 xt shifter? reason for asking is that one option would be to use an XT rear mech and 11-42 cassette with a 105 or Ultegra chainset, and I'd prefer matching shifters. ( I'd like to stick with M8000 parts as I have an M8100 brakeset )


Road gears are generally too high and bmx way too low, I've considered a GRX setup, but that still ends up a bit high. (and, I think needs a specific shifter as the spacing of the rings is unique? which only comes for drops}


I suppose the obvious answer would be to use an XT triple on the front, but would rather a double. Sadly I've bought a wheel with an M8000 hub which won't accept a 12 speed cassette, which would be ideal as a 1/12 setup with a 38 or 40 chainset


Any comments and suggestions would be appreciated


thanks....Pete

mack_turtle

I am confused. what part of this plan has anything to do with BMX?

veganbikes

I don't think this has anything to do with BMX, maybe MTB but not BMX.

If you are looking to build up a flat bar touring bike you have a lot of great options but might need to ditch the road stuff and go to MTB stuff to get the better gearing for loaded touring. With 10 and up Shimano split so Road has it's own cable pull and MTB has it's own cable pull and nary the two shall meet unless going with non-Shimano shifters or mixing shifters.

This is my plan for a 2x11 flat bar touring/gravel bike:
White Industries G30 cranks 44/30 (might go 46/30)
Shimano Ultegra FD-R8000 11-Speed 31.8/28.6 Black
Shimano XT RD-M8000-SGS 11-Speed Shadow Plus Long Cage
Shimano XT CS-M8000 11 Speed 11-42t Cassette
microSHIFT Thumb Shifter Set, 11-Speed Mountain, Double/Triple, Shimano DynaSys Compatible, Black (this allows me to use whatever compatible front derailleur I choose since it is friction front, indexed rear)

The gearing is a bit similar to my current road touring bike (3x9 24/36//48 w/ 11-34t cassette) with a little off the top and bottom end but still does me pretty darn well. If you want the full build kit, let me know and I can send you the spec sheet (though I am not sure what brakes I want to go with)

newredbike

High Guys,
many thanks for the replies, don't know where the BMX reference came from, must have had a "senior moment" as Veganbikes said it related to MTB.
Thanks for the suggestions for a setup, I'll certainly take them on board.
I think the Shimano compatibility chart is perhaps very "safe" in their recommendations , I would quite like to use a GRX 46/30 on the front, and several bike manufacturers (including Genesis which is my frame, use GRX crankset with Tiagra shifter. on flat bars.
I seems that an 11-42 11 speed MTB cassette should work on the rear, but as the GRX crankset has a chainlink offset of 2.5mm a spacer may be needed.
All good fun!
I was pricing up a crankset, over £200 from wiggle, same one from Bikediscount in Germany £79, just hope there's not massive import duties after Jan 1st
Stay safe!

newredbike

Chainlink not chainlink.....autospell!

newredbike

done it again, chainline

Russ Roth

Depends on what compatibility you're looking at. If you mean rear der to cassette size there usually is some play. If you mean shifter to rear der, I tried tiagra 4700 shifters with older 10sp ultegra der and an LX 10 sp and the shifting flat out sucked. Microshift has some solutions to play with, they actually make drop bar levers for MTB der to run gravel and road der shifters for hybrids and flat bar gravel. Veganbikes has a great setup, road cranks shift better with road front der and MTB rear der work best with mtb cassettes for range. Pick the shifter that works from there.

newredbike

Thanks for that,
I certainly wouldn't want tiagra shifters, don't know if they do a x2, the 105 shifters for flat bars are 2/3 on the front recommended as compatible for a 2/11 setup, presumably the distance shifted is common across 11 speed cassettes so an XT.

what I may well do is go for a "trekking" triple ( I know, they're really old fashioned) and an MTB rear setup , Lots of time to consider, Sourcing bits seems difficult at the moment everyone's gone bike mad. Had a hell of a job to source the cdf frame, Spa cycles had just got some in, really old 2nd hand ones on eBay seem to be going for crazy prices.

Thanks again for the comments, nice friendly forum this one
Cheers...Pete

newredbike

Lost a bit there, was saying so an XT shifter should work ?

veganbikes

An XT shifter will work for an MTB derailleur it will not however work with road (or gravel) However if you go with the Microshift thumb shifters you can mix a bit as the front shifter is friction. You can also mix shifters and different derailleurs (that are both the same) for Di2. For instance you can run MTB shifters with road derailleurs or road shifters with MTB derailleurs (but no mixing derailleurs it does not work).

You could look at JTek's Shiftmates but honestly I don't really see a huge want for that in your situation when other better solutions exist: Shiftmate Compatibility Charts and Choices - Jtek Engineering

If you do plan on running GRX cranks you will need a GRX front derailleur because of the spacing differences. Something like the White Industries cranks will not require that.

dedhed

Tiagra 4700, while "10 speed", the shifters and RD use 11 speed pull ratios and need to be used together.

newredbike

Thanks for all the helpful comments, I finally decided that I really couldn't (easily) get the ratios I wanted with a 2/11 setup, so have gone for a complete XT Trekking 3/10 setup, with an 11-36 cassette and 48-36-26 chainset with the matching XT Mechs. That will give reasonable cadence at speed, and with heavy panniers of camping stuff should cope with the hills


Shifters are hard to find, I need ones with "band" fittings as I have M8100 brakes that have I spec EV mountings, and I think only only the latest 12 speed shifter attach to them. SL M780 are recommended, but the band ones seem very difficult to source, lots of I spec ones about, but not the right I spec.


Q, would an 11 speed XT shifter work with a 10 speed rear mech, just stopping when the mech comes to the end of its travel? M8000 2/3 and 11 speed shifters seem available with band mounts., and would be ideal.

Thanks for all the help and suggestions everyone, much appreciated

veganbikes

Awesome, the Trekking group is a nice option sad they don't do it more in the U.S. and do a drop bar option.

Anywho I don't mess with all the odd iSpec stuff my choice would be to go with these: https://www.microshift.com/en/product/sl-m10/. They make more sense for touring as if something goes awry I can set the rear to friction if need be and the front is already friction which I think works way better anyway. However there are certainly adaptors for stuff out there for their iSpec but I would have to research which works with which.

I also wouldn't do anything but the correct shifter. I don't want an extra click, I hate that and in a moment of bad thinking or being tired I could easily accidentally over shift because things changed and it could end poorly. I like 10 clicks if I have 10 cogs in the back.

newredbike

Thanks for that, Strange about the availability of components specific to different countries , all down to marketing I guess? and may be fashion, On the Continent, Hub dynamos are fitted to far more bikes than here, I've always made up front wheels with dynamos, so reliable and always ready to use, great for charging up the phone on camping trips too.

I agree with you about the correct shifter, and found there actually is a specific one for that trekking setup, the SHIMANO Deore XT SL-T8000 Rapidfire Shifters 3x10


Don't know what it's like in the States as far as sourcing parts is concerned, but since the Pandemic, here in the UK, sales of bikes and bike parts have gone crazy, really hard to source parts, I tend to get all my stuff from Germany, which is generally cheaper than the UK, and is usually delivered in less than a week. The exception being the shifters, which are on back order for a month, still no hurry lots to do in the meantime. Converting my old trekking bike ( 1990 Specialised Rockhopper) to an eBike using a Bafang motor, I did have it on a beautiful "On One Pompetamine" with an 11 speed Alfine hub, but that bike was far too nice to desecrate! We're only legally allowed 250W motors here, but certainly helps carrying heavy shopping and living half way up a steep hill doesn't help.t All good fun!

Stay safe,

Have a good Christmas

veganbikes

Cycling in the U.S. is seen as more of a child's thing and bikes are just toys not a meaningful transportation. However we are slowly seeing the light and dynamos are becoming more popular along with other euro style bikes and ideals. Getting parts has been a nightmare for some stuff, the U.S. based manufacturing has been ok, I got my Paul Components stuff pretty quickly and I bet I could have gotten other stuff should I have needed it. Hopefully it will be over by this time two years from now if not sooner but I am not holding my breath unless my mask breaks and I need to move out of an area of people.

A properly built mid-drive e-bike with a 250w motor is just fine. Bosch, Brose, Shimano would be just fine for me. If I really want one of those power gobblers I would get a proper motorcycle and then not be able to ride it except on the road.

Have a good set of holidays as well.