Cyclocross - converting to single ring...advice??

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Scrodzilla
09-15-09, 07:44 PM
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!
:D
ridethecliche
09-15-09, 08:06 PM
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
09-15-09, 08:19 PM
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
09-15-09, 08:33 PM
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
09-15-09, 09:14 PM
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 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
09-15-09, 09:36 PM
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
09-15-09, 09:42 PM
You shouldn't run bullhorns for cross.
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
09-16-09, 06:09 AM
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
09-16-09, 06:52 AM
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
09-16-09, 11:37 AM
You can grind down the teeth on an old chainring and mount it on the outside as the cheapest option possible.
isotopesope
09-16-09, 11:47 AM
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!
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. :eek::)
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. (http://www.paulcomp.com/thumbshifters.html) 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.
As long as my derailleur is calibrated correctly, I should have no trouble, correct?
correct.
Can anyone here recommend a decent, inexpensive outer chain guard and dog fang?
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
09-16-09, 11:52 AM
http://www.bbgbashguard.com/Cyclocross.html
These are a good a cheap option for guards. I have several.
ridethecliche
09-16-09, 12:10 PM
I still don't think bullhorns are the best idea for cross.
Are they even allowed?
bluenote157
09-16-09, 01:18 PM
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
09-16-09, 05:46 PM
I still don't think bullhorns are the best idea for cross.
Are they even allowed?
Haha...are you even reading my responses to your posts or what i wrote in my original post? Not riding cyclocross...just transportation.
:D
Scrodzilla
09-16-09, 06:03 PM
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
09-16-09, 06:13 PM
http://www.bbgbashguard.com/Cyclocross.html
These are a good a cheap option for guards. I have several.
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
09-16-09, 07:53 PM
If you are using crosstop levers, then maybe you can use a barend shifter at the end of the horn??
Scrodzilla
09-16-09, 07:59 PM
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
09-16-09, 08:14 PM
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
09-16-09, 08:46 PM
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
09-16-09, 09:32 PM
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??).
http://goods.us.marketgid.com/goods/41750/
If I've repeated myself i apologize. I had one too many glasses of wine tonight.
ridethecliche
09-16-09, 09:38 PM
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
09-17-09, 06:17 AM
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
09-17-09, 07:06 AM
^ it simplifies things to some extent. No fussing with a FD set up, no cabling, no cross chain rub etc...
Scrodzilla
09-17-09, 11:19 AM
^ it simplifies things to some extent. No fussing with a FD set up, no cabling, no cross chain rub etc...
Precisely. I also find modding bikes to be quite fun. My crankset is a heavy steel-ringed clunker, I have a spare single-speed crankset, my left shifter is crapping out and I have gear ratios I never use. Why not convert to 1x7?
bonechilling - I don't recall asking who would be bothered by my converting to a single chainring or who wants to start some silly fixed-gear vs multi-speed 'battle'. I came in peace asking for some friendly suggestions.
Thanks to those who have been/continue to be helpful.
isotopesope
09-17-09, 11:39 AM
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...
you should probably first try to adjust your front derailleur properly...
speaking of single ring setups, this seems like the ideal single ring chain babysitter:
http://www.paulcomp.com/chainkeeper.html
then you don't need all the bashrings and a third eye/dog fang, and don't have to still worry about the chain hopping up and over the bashring... which i saw happen to a single ring racer last weekend, despite his outside bashring and third eye.
Scrodzilla
09-17-09, 11:51 AM
speaking of single ring setups, this seems like the ideal single ring chain babysitter:
http://www.paulcomp.com/chainkeeper.html
Well I'll be damned...look at that! That thing is simple and perfect (pricey though at 52 bucks :eek:). Thanks for the info.
I knew I could count on you cx guys!
Noobert
09-17-09, 01:01 PM
If your running a triple up front, with out the front derailer, and on the middle ring, its probally not going up, and if it pops off downward, it lands on the smallest chainring
ottothecow
09-17-09, 06:04 PM
Yeah, the paul thing is nice...if I was building a new bike I would spring for it.
If I already had a junk front derailleur...I would use that to save money. I wonder how much weight you could shave off too...you could definately cut out springs and cable attachments...everything except the cage and the set screws (unless you figure out how to weld it in place)
Cynikal
09-17-09, 06:38 PM
Honestly, for road use, I doubt you would need anything to hold the chain on.
Scrodzilla
09-17-09, 06:58 PM
Honestly, for road use, I doubt you would need anything to hold the chain on.
Thanks. I'm going to try without it at first and just take it easy for my first few rides. The Paul thing is super cool but probably a bit too expensive for what it is.
Another (probably dumb) question:
I'll obviously need to shorten my chain some. How do I determine an optimal length?
Scrodzilla
09-18-09, 06:07 PM
Just for the hell of it, I disconnected and removed my front derailleur this afternoon and went for a test ride using only my small (39t) chainring...just to see if I would have any issues with the chain coming off. I was cranking pretty hard during a few gear changes too and I had no troubles.
I think I'll go ahead and put my SS crankset on there and experiment with my 42 and 44t chainrings. I'm thinking I'll like the 44 a bit better. Will I even need to shorten my chain for this setup???
jfmckenna
09-19-09, 07:01 AM
you should probably first try to adjust your front derailleur properly...
speaking of single ring setups, this seems like the ideal single ring chain babysitter:
http://www.paulcomp.com/chainkeeper.html
then you don't need all the bashrings and a third eye/dog fang, and don't have to still worry about the chain hopping up and over the bashring... which i saw happen to a single ring racer last weekend, despite his outside bashring and third eye.
That is super cool. Leave to Paul to solve these problems! If I ever go back to single ring I will be getting one of those.
Scrodzilla
10-03-09, 02:16 PM
Update/new question:
I've been riding around pretty often using my bike 1x7 and have had no issues with the chain falling off even without a ring guard/dog fang. Currently using a 46t chainring and all's good.
I'm really looking to replace my shifter with a bar-mount one in order to lower my stem a touch. Does anyone happen to know of a Shimano indexed 7-speed shifter with a 26mm clamp? All the ones I've found have clamps that are too small to mount on the bulge next to my stem. The Paul 'Thumbie" is cool, but so much damn money!
bluenote157
10-03-09, 08:58 PM
I know you asked for 7 indexed, but i think that this is a friction one that might work.
http://www.velo-orange.com/fafrthsh.html
jtgotsjets
10-04-09, 02:30 PM
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 ****.
Why don't you ride your bike and stop worrying about this ****?
If you're not racing your road bike (most people don't), you don't need to squeeze every last bit of speed out of your bike—I almost never use my road bike's big ring except for a single half mile, slightly downhill stretch of one of the local bike paths. Why should I keep it? (Answer: laziness)
And if you are racing? ****it- shave that weight.
Scrodzilla
10-05-09, 10:41 PM
Thanks, jt. Like I said earlier...modding and wrenching on bikes is fun. Some people are just ********. "bonechilling" is one of them.
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