Mountain Bike Reviews Forum banner
1 - 10 of 10 Posts

·
Registered
Joined
·
45 Posts
Discussion Starter · #1 ·
I could use some help with front shifter and tensioner questions on my "SS" conversion bike please.

I've got a mid-90s Fisher steel frame that I'm converting to a single speed. But, for me though it needs to be a 2x1 due to living in hilly terrain in the SoCal area and that I also pull my son in a Burley trailer on that bike. I don't want to do a 1x X at this time.

I've got Turbine LP square taper crank with 22 and 32 gearing. I've got a King cog with 18t currently (it had been an endless cog 21 t until I got stronger and figured out what I needed) adapted with endless cog spacers and a good chainline on a Mavic/shimano freehub.

So, currently my SS is a 2x1 with 22x18 and 32x18.

Front derailleur shifting, what to use? Thumbie or grip shift?

I'm trying to get the best solution for shifting of my front derailleur. I don't want to do it with my hand or foot and I don't want to use the XT 3 ring trigger that I have. I do want to either use a 2 speed thumbie or a 2 speed grip shifter. Which one would work better? I'm leaning towards the grip shifter because it will be more stealth, can be matched up with a shorter ODI lock on grip (I currently have longer ODIs on the bars), and allows some adjustability of front derailleur as needed.

Tensioner for a 2x1, which to use?

I need a tensioner that gives me good chain wrap around the rear cog (pushes up), attaches to the rear derailleur attachment point, and will do a good job with the 2 chainring scenario. I don't want to use the XT rear derailleur that I have. Which will do the best job for a 2x1: Convert, Singleator, Melvin, Renner, other?

Thanks for any suggestions.
LocoMotoMan
 

·
Mtn Biker Machinist
Joined
·
1,298 Posts
Melvin or old deraileur

The rear tensioner would have to be a melvin or an old deraileur in order to take up the slack of the smaller ring/cog combo when you shift up front. Try to find an old short cage (even a road) derailuer, that is the cheapest solution! Last time I checked, the Melvin was like 60-70 bones!

As for the front shifter, I would go with a gripshift to, easy to adjust and play with, plus it is way less conspicuous than the crappy stuff from that "s" word company! :)

Good luck, and post pics when you get it done!
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #3 ·
Thanks.

I've got either:
An old late 80s Shimano Ultegra 600 rear derailleur (7 speed I think) that looks like a short cage.
An old XTR from the 80s-90 timeframe (shiny smoked finish on it) that looks like a midcage and has metal pulleys and probably shifted a 7 speed.

Which would be better you think?

Regards,
Marc

1 cog frog said:
The rear tensioner would have to be a melvin or an old deraileur in order to take up the slack of the smaller ring/cog combo when you shift up front. Try to find an old short cage (even a road) derailuer, that is the cheapest solution! Last time I checked, the Melvin was like 60-70 bones!

As for the front shifter, I would go with a gripshift to, easy to adjust and play with, plus it is way less conspicuous than the crappy stuff from that "s" word company! :)

Good luck, and post pics when you get it done!
 

·
Registered
Joined
·
492 Posts
What about a 2 speed dingle like this? 34-16 or 32-18. That way you can do away with any derailleurs and just effect a manual shift when necessary. Any spring loaded tensioner would then work fine.

Sam
 

Attachments

·
Mtn Biker Machinist
Joined
·
1,298 Posts
tighter spring

Whichever has a tighter (ie snappier) spring, less chainslap that way.

To size the chain, put it onto the biggest ring and pull it as tight as possible, even if the cage is almost touching the chainstay, then adjust the high/low screws to get your chainline on.

Looking at the gearing, you are gonna be spinning like mad running 22:18, but give it a try. You may want to look at going with 32:18 and 42:18 instead, but you will have to figure that out after riding.

Good luck, post pics!
 

·
Registered
Joined
·
836 Posts
sounds sketchy....why not just run a 1 x 8?

wouldn't adding a derailleur make it not a single speed?
 

·
Registered
Joined
·
2,822 Posts
1 cog frog said:
The rear tensioner would have to be a melvin or an old deraileur in order to take up the slack of the smaller ring/cog combo when you shift up front. Try to find an old short cage (even a road) derailuer, that is the cheapest solution! Last time I checked, the Melvin was like 60-70 bones!

As for the front shifter, I would go with a gripshift to, easy to adjust and play with, plus it is way less conspicuous than the crappy stuff from that "s" word company! :)

Good luck, and post pics when you get it done!
yes, agree with cogfrog completely!
You'll have to run a melvin (works well for me, either w/ finger/heel method or an old thumbie, since I didn't have any gripshifts around) or a derailleur... Any old short cage derailleur will give you better tension, road or mtn, maybe your LBS will even have something in the parts bin for free or cheap.
 

·
Registered
Joined
·
17,609 Posts
I say use a derailleur for tension, and do away with the front shifter completely. Use your right heel to nudge the chain down onto the granny and use your hand to bring it back up onto the 32T ring. This way you get the nice, clean handlebar (meaning without shifters) and since it'll be a bit more effort to shift, you'll be more likely to just leave it in the 32T rind and grunt it out (for the SS experience and quick fitness gains). Before long you probably won't even need to use that granny.

This is how I did it when I first started. I had that bail-out gear for steeper stuff and to tow my kid around, but I no longer need the granny.
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #9 ·
Thanks for the suggestions and discussion. I'm learning a lot!

Well, then I'll need to be alternative. I need the 22x to go up the hills or while towing my son in the Burley so that adds 50+ lbs now as well as up the hills behind my house here in SoCal. The 32x for the flats or downhill and eventually the uphill will be 32x as well as I get stronger. So, with my current bike stable I need to keep the bike as a 2x1 for now and work within my area and my abilities. So, a short cage rear der sounds like a good solution, and the grip shift won't show the thumbie on top and will integrate nicely with a shorter ODI lock on when compared to the other side. Bike is not going to look clean anyway because it also has lights on it front and rear, bar ends with incorporated mirrors to watch the boy and cars, and the rear skewer for the trailer hookup. It's an all purpose steed since I'm just now exploring this SS thing. My other bikes are dedicated gearies (Titus LocoMoto and Yeti ARCTi). They all give me great pleasure around SoCal and elsewhere up, down, sideways etc.

And, if I like this then the current 2x1 may be retired to trailer towing with gears and I'll get a separate dedicated SS bike.

Best regards,
Marc

Nat said:
I say use a derailleur for tension, and do away with the front shifter completely. Use your right heel to nudge the chain down onto the granny and use your hand to bring it back up onto the 32T ring. This way you get the nice, clean handlebar (meaning without shifters) and since it'll be a bit more effort to shift, you'll be more likely to just leave it in the 32T rind and grunt it out (for the SS experience and quick fitness gains). Before long you probably won't even need to use that granny.

This is how I did it when I first started. I had that bail-out gear for steeper stuff and to tow my kid around, but I no longer need the granny.
 

·
a.k.a. MTBMaven
Joined
·
1,750 Posts
I'm currently running a 2x1 set up. I've got a 32/22 and 17 in rear. Wish I had a larger cog in the rear for SoCal's steep trails. I'm using a XT shifter and an LX front D with a Melvin tensioner. Up shifts are sharp. Down shifts suck and sometime I need to use my heal. I think this is the result of a POS front D. I need to get one of the newer high mount XT front D. All in all I love the set up. Long live 2x1.

Oh make sure you use a bash guard. If not you will overshoot on the up shift and drop the chain.
 
1 - 10 of 10 Posts
Top