tonka.toy

for about the last 3 months I haven't bothered to change gear on the front drive, the 9 or should I say 6 cogs at the back that I do use seem adequate for my road needs. The bike has 26" wheels and has pretty much standard MTB drivetrain components.

Here's my thought, replace the standard crankset that came with it with one of those kinky Hollowtech II units, I'm looking at the Hone because I'm vain and like the black. I'll ditch the front derailleur, changer and small and inner rings. The Hone come with a 44t ring which will go on ebay with the others and I'll use the 48 Ally ring that I have at the moment.

I'm hoping that little lot should save me best part of a kilo and I might switch to a 50t ring, chainstay permitting.

I've been told that I'll have skipping problems without the derailleur. So what do you all do if you only have a single front ring, chainguides? what other potential problems can you see looming.

Steev

I took a more simple approach for my 1*7. I just removed the unused chain rings, FD and shifter. No problems with the chain coming off the chainring, but then my other bikes don't constantly ghost shift the front either.

pinkrobe

I don't know why you would have skipping problems without a front derailleur. If it doesn't skip when you're riding normally [assuming your chain isn't rubbing against the derailleur already], then you should be fine.

max-a-mill

i don't think mtb cranksets and 50t rings match though...

https://www.sheldonbrown.com/harris/chainrings/104.html

although you may be able to find bigger it seems you'll top out at a 44t.

martianone

have a 1x9 with 42x622 tire.
removed the front derailleur, shifter, cables etc. put a 34 t in the
middle position, a chain guard in the outer and a "dog fang" guide
on the lower seat post. don't experience any skipping problems
and don't miss the other gear ratios.

Philatio

I've noticed I will throw my chain relatively frequently (once every 2 or 3 rides maybe? usually it follows a big bump or something - this is a road bike) when I go 1x6 with no FD. This is compared to never with the FD there. just my .02

max-a-mill

yeah my gf's never stayed on either... exactly as you describe.

finally i rigged a front derailleur in just the right spot so the chain can't jump off and it is perfect!

tonka.toy

Thanks all,

fellow commuter in the office has just done this and he gets the odd jump. especially since in smaller cogs at the rear.

I like the idea of clean lines and being able to remove the front derailleur. We've looked at the various chain devices but that just seems like a way to spend money on something that looks like a derailleur.

BTW I currently have a 48T ring and feel like I need more, Those frenchies at TA make some rings 50T plus with a 104BCD.

I think I'll make the changes then suck it and see.

bbattle

You may consider taking a link or two out of your chain.

trackandtrials

+1

I had a 1x8 setup for ~6 months, on a roadish commute, with nary a drop. I attribute this partly to tightening the chain up as much as possible, and partly to the huge, shock absorbing tires I use. If I was riding trails or lots of rough road, I think I'd probably use some sort of chain guide.

nashcommguy

Yes, do it. I've got 2 bikes(road + mtb) set up this way. Road is 52t-28x12, mtb is 46-28x11. Had a problem w/t chain jumping off both. Did the classic big-big+1 chain length which helped a little, but it wasn't until I added an extra chainwheel the same size that the problem was completely eliminated. The drive chainwheel is located to the outside on both. Got the idea from an lbs mechanic who's also a commuter. A smaller der will help, too.

tonka.toy

sounds kind of unique - I like it, any photos? What's the idea behind it.

adamtki

A chain guide or chain guard would help keep the chain on, but I can't find one that'll cover a large chain wheel. bikeman sells some of the smaller ones.

https://www.bikemannetwork.com/catego...CH&store=1&p=2

I rode without a FD and the chain would jump off once in a while. I've been looking for a very light single chain crankset that can hold 49-52t

Brian Ratliff

It's probably fine as long as you use an engagement track ring (like a Rocket Ring or Salsa engagement ring) instead of the usual shifting rings. Engagement rings have higher teeth and are not designed for the chain to derail.

On my two geared road bikes, I don't "auto-shift" the front very often, and mostly when I am cross chaining, but it does happen once or twice every month or so. With a two or three ring setup, it's no big deal, you just use the derailler to get the chain back on the ring you want. With a single ring, you'd have to stop and get it back on with your hands. It's also prone to happen at the worse possible moment, like when you are dashing through an intersection and can make you lose control of the bike.

cerewa

At least some of the chainrings designed for single-speed use can't be used with multispeed chains. I tried to put a 6-speed and cog set on a bike with a single-speed chainring and the chain wouldn't fit on to the teeth; the teeth were too fat.

grolby

This is just a matter of knowing what you're looking for. There are lots of single speed chainrings available in 3/32", which is becoming more and more of universal standard. Just be sure to check or specify the width on any chainring you want to use or purchase!

nashcommguy

Hey Tonka.toy,
Sorry to have taken so long to post back. No pics as I don't have a di-cam or scanner. My pc is pre-historic and I'm still using dial up as I live rural and there's no 'ports' here for dsl/fast access. Ok, enough of my probs, let me see if I can adequately describe my set-ups.

First off the suggestion above to try a Rocket Ring is a good one. And probably much simpler than what I've got. The teeth are much longer as they aren't designed to derail. Bikepartsusa.com has them available in different sizes for $30-35US. I didn't want to spend the money so I opted for the 2nd chainring which acts as a chainguard/limiter. As you shift down the release of tension can cause the chain to 'snap' from side to side like a garden hose given a shake. On chainrings designed to derail the teeth are much smaller. When a 2nd chainring of equal size is added the chain is prevented from snapping too far and falling off. Mine was always falling off to the inside so I added an old 46t from my parts bin. It's from a touring set. The problem doing this with a standard mtb set up is the length of the spindle. You need to find an extra long one to allow for the extra size of your 2nd chainring. On mtb's standard 24-34-44 the clearance isn't there for a bigger chainring by the chain stay. Again, I found an old spindle in my parts bin from what must've been a touring set. Gave me JUST enough(1/8")clearance. So, I've got 2 46t chainwheels on the front w/no der. The rear has a stock 28x11 7 sp mtb cassette and the chain is stock. The chain still 'whips' when I do a hard shift, but hasn't popped off in about 3 years.

The roadie is an old steel frame. The chain was always popping off to the outside, so I did just the opposite of the mtb. The drive chainwheel is to the inside and the 'limiter' is to the outside. I've got an old Sora 7 sp brifter, so I've been able to watch the chain action while shifting. It still 'whips' but the 2nd chainring prevents it from jumping off. I've got 2 52t chainwheels w/no front der and a 7 sp 28x12 cassette w/a KMC chain. The chainwheels are from my parts bin. The chainstays gave plenty of clearance, so there was no problem using a standard road spindle.

Can't lay claim to this idea. It's simple, ingenious and effective.

Brian Ratliff

Ah... you got yourself a 1/8th inch thick chainring. There are two standards for single-speed: 1/8" and 3/32". Officially, 1/8" is the track standard, while 3/32" is the width of the narrower derailler chain. Make sure you get the 3/32" if you intend to use shifting chain on this ring. Rocket Rings accomodate the 3/32" standard.