To kind of go along with my Mountech front derailleur thread- I finally mounted my second generation Mountech rear derailleur to my 1985 Trek 720.

As many are aware of the legend of the "Curse of the Duopar," Suntour's Mountech derailleur was an attempt to chase the performance of Huret's Duopar triple pivot derailleur. As with a few other innovations of this time- the engineers at Suntour attempted to be clever and created an enclosed spring loaded upper guide pulley. However, that enclosed pulley had a propensity for attracting dirt and then seizing up at inopportune moments. Because of it being enclosed, it was also exceptionally difficult to replace/repair. This was the beginning of the end of the reign of Suntour- the bulletproof reliability that surrounded Suntour was damaged.

The engineers at Suntour made some changes and re-released the Mountech; primarily the upper pulley was changed to a normal Maeda Industries pulley- to maintain the "cleverness," the lower pulley was a 13T pulley- and in addition to the long cage- it had a capability to wrap an OUTRAGEOUS amount of chain. Combining the colossal amount of chain wrap with the triple pivot design- that meant the derailleur could handle a huge cog- and take up chain for a large front chainring as well as a small granny- a true wide range derailleur.

Of course they used the same name. I don't know why they just didn't come up with a new name. Of course, it wouldn't have mattered- Shimano had SIS brewing up. Reliable indexing or wide range derailleur?

I had cleaned up and put together a triple pulley Suntour XC rear derailleur. I kind of did it as a bit of a joke- but that derailleur worked REALLY well.




Pastor Bob expressed a bit of interest in trying out the 3 pulley with some of his monster cog freewheels- so I pulled it off this weekend and thought about what derailleur to replace it with. After running something as cool and unique as the triple pulley XC- I wanted to use something cool and unique. I thought about putting the XC Pro (with "titanium" Bullseye pulleys) back on it, but I was looking for a bit more uniqueness with that kind of reliability. I mounted the LeTech- but I couldn't adjust the unit to get to the outer cog consistently. There's room on the limit- it just won't go out any further. I didn't feel like dicking with it, so I put on the Cyclone MII that Flog00 sent to me- and for whatever reason- that derailleur felt... "dainty" on my bike. As reliable as the MII Cyclones have proven to be, I wanted something different and a little more burly. I actually fitted the stock Titanium Huret Duopar- but realized I wanted "reliable" more than "unique."

After a little bit of preparation- I mounted the Mountech. I really had no intent to actually use this thing when I got it- I was more or less after the front derailleur- the set was an extra $10 more than I was willing to pay for the FD alone. After I got it on the bike- I trucked around- and this thing actually shifts really nicely. Even going into the granny and the smaller cogs- this thing wraps so much chain, the cage barely goes backwards!

I would imagine there are many C&V people that would never be caught with a "Mountech" RD on their bike- but I'm really digging having this on there right now!

And, in accordance with International Interent Rulez: Pix or it didn't happen:






I've got to replace the cable- all that pinching and unpinching started the cable fraying- but that's for tomorrow!

I've had a few of those on bikes and they work alright. I think mine was the third iteration of them.

What does the third version look like?

It's late now, so I'll have to look back through my research. I think Disraeli Gears talks about it. Mine matches the image of the third version. They "fixed" what was wrong with it. I can take a photo tomorrow or so.

First came the 4900 (1982), then the longer cage & redesigned 5500 (1982), then the Mountech II (1985), which is this one, and the one I have.

https://www.disraeligears.co.uk/Site/...erailleur.html

Rolling the dice praying in foxholes buying Lotto scratch off tickets riding a MounTech all part of the wild and crazy life of our own [MENTION=174646]The Golden Boy[/MENTION]!

Seriously, you are a tinkering dude's tinkerer!

One of us needs to develop a fully enclosed chain case for the MounTech RD arm, something similar to those cases we see on the old Raleigh bikes. Only we'd make it out of CF or some other modern composite.

So last night, as I'm drifting off to sleep, I'm thinking "I could take that huge pulley, put it on like my Superbe Pro RD and then I could use that on a triple and then... zzzzzzzzzzzz."

Rocking some Accushift housing even. Keep the dream alive!

I look forward to see just where you take this (the derailleur as well as the bike).

Definitely watching this thread. I really like these experimentation posts, and love hearing what works and what doesn't. I only wish you had snapped shots of each setup showing the relative swing of the pulley cages in a set gear. Also,if you could work in some Jan Heine-esque charts and graphs that'd be awesome. Kidding on that last bit, although I do love the articles in BQ.

Ha!

Did you see my awesome thread about using too low of a gear for my chain?

https://www.bikeforums.net/classic-vi...ack-chain.html


Seeing as how it worked with the Stronglight crankset, and I realized that 24t granny was REALLY small- I put a 30 on and it worked- I've got a 28 coming.

There was a nice young man here who used to post videos of his derailleurs going through the gears. I think it's interesting to see how different derailleurs handle the extremes- and what different derailleurs see as "extreme."

There's also my 3-Pulley adventure- which is actually what spawned the use of the Mountech II.

https://www.bikeforums.net/classic-vi...y-project.html



Again- these derailleurs are interesting in that they were evolutions of what Suntour had been innovating, responding to ATB and MTB needs for lower gears and ground clearance- but yet keeping the option of higher "road" gears available. However, when SIS came- all that mattered was clicky shifting. If there was a reliable indexing shifting system, they could have branched out from there- but Shimano seemed to do really well with the Deore derivatives.

With the 3 pulley thing- I did it more or less as a joke- and I was struck by how well it worked. Because I only use two bikes with friction shifting right now- this bike was perfect for it. Not only is the 1985 Trek 720 a Flagship level bike with the nicest, purpose driven frame Trek came up with- it also had among the very finest in components available- regardless of manufacturer. I've "upgraded" things on the bike to things that I felt were nicer or more handy or looked cooler- to include a circa 1993 Suntour XC Pro RD- but that XC 3 Pulley performed as well as the XC Pro, and it was much more interesting. It's made the decision of which derailleur to use much more difficult.

Using the Mountech II (I don't know if it actually was considered the Mountech II- it's still just "Mountech" on the derailleur) I'm struck by how nicely it works. If you're a dork like me, you know of the colossal failure of the Mountech- you know of the impending cloud of doom that will hover over you and cause your demise... Again, I've had this Mountech sitting in a bin, there have been a few people I was going to gift it to- to replace first gen Mountechs. I've had it and never noticed the huge pulley. As cutesy as it would be to use these dead-end curiosities- they also work REALLY well. I think the 3 pulley would be more robust than the Mountech- three pivots and and a huge, unsupported cage does carry a possibility for catastrophe with it.

I'd like to figure out what's going on with the LeTech- I want that computer font of the future to be featured on my bike!

Yep, followed both of those with great interest. You're throwing some great content on here, please keep it up! Hard to be too controversial with this sort of super-interesting experimentation. Unless of course you somehow managed to start a "3 pulley Brooks 531 friction vs modern retro tech carbon framed upgrade" thread. Now that'd be funny.

ALL the housing on here is Accushift!

Really like Accushift housing, and I have a dwindling stash of it, enough left for one more bike. Seeing that I do not use indexed shifting on any of my bikes, and have always used it on the wife and kids bikes, it should be around for a few more years. My old friend Ray had the triple wheeled rear derailleur set up on a 4 ringed front end. He used it on his commuter bike, a 1986 Miyata Terrra Runner. Crazy gear range, and it worked. The front shifting was tough for the Mountech front der. but worked well for what it was, except when it became iced up in the winter. Truly a great der. design both front and rear. I still use a Mountech front on my commuter bike. Probably the best shifting front der. I have ever had the pleasure of using.