80" Gear

[ABlipInContinuity]

Off my rocker me thinks.

After 'loosing' my last fixie (   ) which had a 74" gear, I specced the replacement with 16 and 18 tooth fixed cogs, giving me a choice of 70" or 80" gears with the as supplied 48t chainring.

I upgraded the wheels and my replacement rear hub is only single sided, giving a single choice of gear. I've opted for the 16t, having found that I quickly adapted to the first fixie and didn't find any climb a choir.

I have to confess though, I've felt "pushed" after the first few trips out on it. I haven't felt any strain on my knees though and I think in a week or two I'll find myself quite accustomed to it. This bike is easily a couple of kilos lighter than the outgoing one, so I even think the climbing will be okay.

So, is this lunacy or will I stay sane?

I've stripped down the geared bike (can't bear to part with the frame) in order to sell the bits and fund the tandem. For now, the fixie is the only road bike in my fleet.

[Greenbank]

There is no right or wrong.

If you pick too high a gear you'll end up walking too many hills. If this is too annoying then you can gear down or put up with it.

If you can push the big gear up all of the hills then good for you.

[border-rider]

70" on a light bike is fine

80" is bigger than I'd be comfortable with.  Round town I'd gear in the 60s, but if it's flat terrain I guess 80 could work  for you.  Whether it's the best option is your call.

[giropaul]

Get a 17 sprocket - 76" which is pretty close to your old gear.

[Blah]

The thing I'd be more concerned about than hills is headwinds, especially in winter.

Also, climbing an 80" gear in dry weather is not the same as doing the same on a wintery, salty, wet road. There are some roads where I have to climb seated to avoid slippage.

Not that hard to change a sprocket though, so might as will keep going with it until experience proves otherwise.

[rae]

I run 81" in London, but we don't have proper hills here.   I can shin up Pentonville road at a fair clip.   Rides about town are short - there is a world of difference in being on the wrong gear on a 5 mile ride vs a 20 mile ride.  +1 on headwinds.

[токамак]

I generally ride 48/16, on 700x23 with 165mm cranks, which, using Sheldon Brown's Gear Calculator actually works out at 78.8 gear inches. I ride round Essex which is mainly flat but there are a few steep-ish hills around which I've not had a problem getting up, although saying that it can be quite a slow going, out of the saddle, slog at times, and I have had a couple of occasions in the wet when I felt the rear wheel slip a bit (but maybe that's because I ride on Conti Gatorskins!).
Also, some people have pointed out to me that with 48/16 you can get uneven wear on the sprocket and tire. I don't really think this is an issue though as whenever you re-tension the chain you can move the wheel round a touch.

Obviously, if your knees do start to complain then you should change to a lower gear, even if you otherwise feel strong enough to push 80".

[woollypigs]

I used a 83"(ish) gear in London for a while, and most roads you can easy ride up and down with that.

[Hot Flatus]

80" is great for my undulating commute, there are a few hills but they are so short that they are sprintable.  Any lower a gear and I probably wouldn't bother, so it makes me work a bit.

Same gear is fine for flattish longer rides, 50 or 60 miles, but I wouldn't want to use it for anything other than the above.

[rogerzilla]

I use 48 x 18 (70" on skinny 700c tyres), which is yer traditional medium gear.  80" is a bit headbanging, although I do TTs on 90" and seem to get to the start line and back without too much trouble - it is unremittingly flat between the clubhouse and the course, though.

[rogerzilla]

Also, some people have pointed out to me that with 48/16 you can get uneven wear on the sprocket and tire. I don't really think this is an issue though as whenever you re-tension the chain you can move the wheel round a touch.

The Frankendale is a theoretician's delight; 39/14 is an irrational number.  It still runs much rougher than the Fuji - there's a reason track chainrings settled at around 48T, and the lower chain tension of your bike outweighs the effect of non-coincident teeth on mine.

[Fixedwheelnut]

 I have been riding around on my Graham Weigh TT bike with an 88" gear, since the last TT of the season I have flipped the wheel around so it is back on 83" gear.
 Big gears are OK for short rides, commutes, 40 mile club rides and TTs but I don't know about an Audax on it 

[Treewheeler]

Well then...
 I weigh 62kg
Height  1m66cm.
Slight build...
Won all my 2nd cat points on steep climbs.
I am geared to 66" what is 42x17 on 32mm tyres.
How any-one turns larger outside of the track is beyond my ken...

[bobajobrob]

70" is my normal gear for flatish rides. I'd want something lower for hilly rides. 80" is too big for me, unless it's dead flat.

[MSeries]

44x17 on 25 or 28mm tyres is enough for me, bit hilly round here

[Fixedwheelnut]

Well then...
 I weigh 62kg
Height  1m66cm.
Slight build...
Won all my 2nd cat points on steep climbs.
I am geared to 66" what is 42x17 on 32mm tyres.
How any-one turns larger outside of the track is beyond my ken...

 I usually Audax on 46 x 18 23c tyres 67.5ish " gear 

[Chris N]

I've never ridden anything over 69" - was having lots of fun off road this afternoon on 57".

[ABlipInContinuity]

Thanks for the points of view.

I've come in today from a day of mixed riding, including Critical Mass, with no complaints from the engine at all. In fact I managed a 5 mph climb (forced pace) over a bridge with a strange cobbled surface (not great for traction) with relative ease. Had to skoot a bit with some really slow starts though.

I like to keep pace with traffic and I find this gear is great for that. I go from a standing start to i'm guessing high twenties (no computer) with no problems. I used to spin out on the 74" gear and wound up playing leapfrog with the traffic. I know I can spin fast too, I used to have a cadence sensor with the computer on the geared bike and I know I can top 130-140 rpm.

I accept I'm not going to be doing any audaxes on it soon.

I accept dropping down to a 70" might be best for the winter, although I semi-hope a hack bike will have found it's way into the stable by then.

Any recommendations on a lock ring tool and a track chain whip?

[Charlotte]

Get the Dura Ace track chain whip - it also does lock rings.  Will at Hubjub will get you one.  You'll never want for another one as long as you live.

By the way, I'm a 48x18 fan as well.  One tooth more on the back sometimes for hilly audaxes.

[rogerzilla]

My LBS sold me a small cheapo peg spanner (it has a sort of hinged dog) which does the trick - lockrings don't have to be done up terribly tight, not do they tighten up in use.

I've posted a photo of The Mother Of All Chainwhips before.  Steel bar from B&Q, some bits of old 1/8" chain, a drill and a hammer.

[Greenbank]

I used to spin out on the 74" gear and wound up playing leapfrog with the traffic. I know I can spin fast too, I used to have a cadence sensor with the computer on the geared bike and I know I can top 130-140 rpm.

I had a similar thing and put a larger gear on to compensate. IMHO it's just masking the problem of not being able to spin fast enough.

I've since geared back down (74.5" down to 67.4") and this has forced me to learn to spin properly and my max cadence has gone up to over 160rpm.

There's still some way to go before you get to FWN levels of 200rpm+

[Chris N]

Any recommendations on a lock ring tool and a track chain whip?

Screwdriver, hammer and reverse-rotafixa.

[Fixedwheelnut]

I used to spin out on the 74" gear and wound up playing leapfrog with the traffic. I know I can spin fast too, I used to have a cadence sensor with the computer on the geared bike and I know I can top 130-140 rpm.

I had a similar thing and put a larger gear on to compensate. IMHO it's just masking the problem of not being able to spin fast enough.

I've since geared back down (74.5" down to 67.4") and this has forced me to learn to spin properly and my max cadence has gone up to over 160rpm.

There's still some way to go before you get to FWN levels of 200rpm+

  Ha ha I have only managed that once and it was not for long even 190 + is only on a good day where a combination of loose legs, smooth road surface with a good view and preferably a steep hill that dips and goes back up again so you don't need to touch the brakes. 

 A more common figure is 160-180 for short downhill periods, a longer hill see's me braking to keep it to a lower 130-150.

[Chris N]

FWN, if you're ever in the East Midlands, try here (190+) or here (197).   Still wondering if I'll ever get to 200...

On a very little gear, mind, so my top speed wasn't much over 55 km/h in both cases.

[Fixedwheelnut]

 I have been through that area a few times on Permanent 600s using the middle road mesh to Lincoln there are a few around there.

 I usually have the North Downs around here to keep the thighs warm.