Scrodzilla

Hello all in cyclocross world. In addition to my fixed gear, I've got a 14-speed road bike...which is quite ridiculous considering I only use about 5 of them...and would like to look into possibly converting it to one ring up front and keep the 7 in back (I posted about this in the road forum but they weren't very friendly). A few folks suggested cyclocross stuff so here I am, giving it a shot.

Through some light recent research, I've discovered that a lot of you guys are running one ring up front. Is it as simple as running a single-ring crankset ( I have an extra one that accepts the ring either in front or behind the spider) up front with a ring guard and a chain guide on the inside? Can I keep the 7-cog cassette I already have? What about shifters? If I'm shedding my front derailleur, I'd love to also be rid of my clunky stem-mount shifters (which barely work). I'm not looking to ride this bike cyclocross...just on the road...so I don't feel I need a super heavy-duty mud-proof shifter. Any suggestions?

Responses are appreciated in advance!

ridethecliche

The issue you might have with running the ring on either the outside or the inside is the chainline.

Shouldn't be a huge issue though.

What kind of bike is it?

Scrodzilla

It's a Dawes Lightning Sport. Nothing at all fancy, but I got it for free from a friend some time back, had it repainted, upgraded a few parts here and there and I like it quite a bit. The 14-speeds is just sort of redundant because a few of the ratios feel super close (if not identical) to each other and I'd like to simplify a little by bringing it down to a straight 7.

Judging by where my chain is when using the small ring (which I usually do) I feel that if I put my ring on the inside with a chain guard on the outside, I shouldn't have much trouble with chainline........I hope!

jfmckenna

You will still need some sort of mechanism to keep the chain on the front ring from bouncing off. I raced for years with a single ring set up with an old front derailleur set down real low and with the pivot points just right so that the highest and lowest cogs won't cause rub. That should be easy to do on a 7 speed set up. And a 1 x 7 is an excellent set up for cross racing. I ran a 1 x 8 with a single barcon and I actually miss it a a lot. I don't like my 2 x 10 at all for racing but it works well on the road so I keep it around. The other option is to have inner and outter chain ring guards or at least an outer guard and a dog fang or other some such inner chain drop guard.

The inner and outer rings are by far the best.

Scrodzilla

The outer guard and fang is most likely what I'd go for because I already have a decent spare crankset that would easily accept a ring on the inner and a guard on the outer.

As far as shifters go, will it be easy to find a single, right hand 7-speed thumb shifter that I can mount either to my bars (I'm running bullhorns) or to my 1" quill stem?

ridethecliche

You shouldn't run bullhorns for cross.

If you want flat bars, go with an MTB rear shifter. For drops, you can use a bar end or an old sora shifter.

I think 7 speed will be harder to do than 8.

Scrodzilla

I'm only using this bike on the road under normal riding conditions. I can imagine that bulls would be no good (and even dangerous) for dirt riding! Just asking some advice on how to properly lose a chainring and some unwanted/unnecessary gear ratios.

Is 1x7 uncommon?

jfmckenna

yes 1x7 is not very common but 1x9 or 1x10 is very common. You won't be able to fit a MTB thumbie on a bull horn because most likely it will be the wrong diameter clamp. I have found some that work but they are hard to come by. Paul makes some thing called the..err umm I don't remember now but it basically lets you mount a DT shifter to your bars, google will find it. Then there are barcons but that might be awkward on bull horns. Run them in friction mode and it doesn't matter how many cogs you have.

Scrodzilla

Through some eBay/Google searches I've found a number of smallish thumb shifters that can be run in friction mode with various-sized clamps. I'm hoping to find a shifter that can be mounted near my stem on my bullhorns (26mm clamp) or directly to my stem (which I'll most likely have to shim in some way). In the meantime, I'll use just the right side of the stem-mount shifters on the bike now. I suppose a trip down to the city co-op to dig through the parts bins is in order!

As long as my derailleur is calibrated correctly, I should have no trouble, correct?
Can anyone here recommend a decent, inexpensive outer chain guard and dog fang?

Apologies if these questions seem a little elementary. Despite being a bike enthusiast for about 26 of my 36 years, I don't know too much about all these damn gears and things......

famous amos

You can grind down the teeth on an old chainring and mount it on the outside as the cheapest option possible.

isotopesope

mountain bike shifters are typically designed for a 22.2mm clamp, which is the diameter of mountain bars at the handle area, but your bullhorns are probably 23.8mm at the handle area. you might be able to "manipulate" (i.e. bend or file) a mountain bike shifter's clamp to fit the larger diameter.

if you have a quill stem, the quill would more than likely be 22.2, so a thumb shifter could mount there.

the part paul makes for mounting a barend/downtube shifter to a handlebar is a called a thumbie. they sell a single one for 35. sort of pricey if you're trying to keep to a low budget. however, they only make them in 22.2 and 26.0 clamp sizes, so you'd have to have a wide enough bulge at the clamp area of your handlebar to accomodate the stem and shifter mount. sometimes that bulge is only about as wide as the stem's clamp...

as long as you're not running tt brake levers, the other option would be to mount a barend or barcon shifter to the end of your bullhorn. you can find them on ebay in various speeds. 7 speed ones are sort of rare or are "vintage" and can get pricey. any speed shifter would work in friction mode however.

correct.

well, as jfmckenna reccommended, you could just leave your front derailleur on there, locked out so not to rub when in the highest and lowest gears... then you don't need a chaingaurd or dog fang. you may not need any of it, as long as you're not hopping the bike to cause the chain to jump.

you could grind teeth off of an old chainring to make a guard. to purchase one, you'll probably spend around 40 smackers.

chain watchers are cheap. probably 10 bucks at a bike shop. i've made one out of an old reflector mount before...

Cynikal 

https://www.bbgbashguard.com/Cyclocross.html

These are a good a cheap option for guards. I have several.

ridethecliche

I still don't think bullhorns are the best idea for cross.

Are they even allowed?

bluenote157

I dont think the op is going to use it for cx...just the road. If that is the case, you don't need a front derailleur. I dont think the chain will pop off. I'm running this right now on a road beater and it never has come off. Just keep the links as few as possible to keep the derailleur tight.

I'm using the inside chainring if that is of interest.

Are you going to be running friction or indexed. I want to say that you can always throw on a barend and shift from there. However, if you are running bullhorn brakes that require the same opening, you might want to go with a single downtube or a thumbshifter. However like others have said, thumbshifters are for mtn 22.2mm tubes unless you go paul thumbies and use your existing shift levers.

i have an old moustache steel handlebar and managed to get a thumbshifter on the end (ala barcon).

Scrodzilla

Haha...are you even reading my responses to your posts or what i wrote in my original post? Not riding cyclocross...just transportation.

Scrodzilla

Thanks so much for the responses, guys. It's appreciated. My bullhorns do have a fairly wide clamp area, so a 26mm shifter would mount there with no trouble. I do currently use a set of cross-levers with a 26mm clamp that are mounted there, so a shifter with a 22.2mm clamp mounted to my quill stem would be perfect.

My current shifter is friction and I don't necessarily need to go indexed (although it may be nice).

If the consensus is that I may not even need chainguards and all that, I'm thinking of throwing my single-speed crankset on there, experimenting with chainring inside/outside of the spider and using my current shifter until I find a single, right-side shifter that can be mounted to my stem. Is there a way to remove the left side shifter so it's not just lingering uselessly?

I don't mind spending a little bit of money to get this done right and I would like it to look nice, as long as it doesn't end up costing me as much as a new bike would!

Scrodzilla

This is awesome. Thanks! The 'Superlight' is only 12 bucks. Even if I don't end up needing one, I may consider one just because it looks cool.

bluenote157

If you are using crosstop levers, then maybe you can use a barend shifter at the end of the horn??

Scrodzilla

I was thinking that, but I'm comfortable with my shifter at the stem so I feel it's the best option to keep it there. Besides, I do have a set low risers (with another set of smaller-clamp cross levers) that I throw on every now and again just to change it up.

You've been especially helpful thus far bluenote. Thanks!

bluenote157

what kind of stem shifter do you have? have you tried to disassemble it. Maybe you can clean it up/grease it up and see if the shifter works better. If it does, then you are set..just remove the other one and grind down the post.

Have a look at paul thumbies..you can get the right size clamp and use that shifter arm...maybe??

Scrodzilla

My current shifter is just a low-end Shimano and it doesn't look like it would come apart without breaking it. It's the one on the left that barely works...the right one isn't so bad. I'm not a butcher and have pretty good mechanical abilities so I'll remove it from my stem and look more into how it might come apart. My stem is a 1" quill...I'm hoping to find a shifter to fit. If not, a Thumbie looks like a cool option.

I'm also wondering...what would be an optimal gear to have up front? I have spare 44 and 42t rings laying around and feel that either of these would work out alright.

bluenote157

i am running 42 front and 12/26 in the back and it works out for me. What number of teeth are on your rear cassette?

If you can salvage the shifter, you might be good to go.
If you take it apart and there is a post, you might be able to just screw another shifter on it...if there is some sort of stop to hold it in place??
Now that i think about it, paul thumbies are kind of expensive and you dont even get a shifter. So you would be paying upwards of $35 + $15(for the shifters on ebay??) and you will end up not even using the second shifter. That is unless you put one of the levers/thumbies on your bullhorns and the one one on your riser bar setup for when you want to use it?? Of course, this has to be all friction.

Lastly, have a look on ebay for suntour "mighty" retrofriction thumbshifter. I have one on my ride and it is pretty cool to use. It is 22.2 clamp but might work out on your stem?? Looks like this but is the right one..although i think this left one would work too(somehow??).
https://goods.us.marketgid.com/goods/41750/

If I've repeated myself i apologize. I had one too many glasses of wine tonight.

ridethecliche

After dropping my chain like 8 times tonight in 5 minutes, I think I might want a single ring...

OR I should just adjust the FD on the bike.

Decisions...

bonechilling

Why are fixed gear riders who are now branching out into road bikes so insistent on only using a single ring up front? Obviously it makes sense for CX, but why someone would want to do this on the road is beyond me. Just ride your bike and stop worrying about this ****.

jfmckenna

^ it simplifies things to some extent. No fussing with a FD set up, no cabling, no cross chain rub etc...