CNRed

Rebuilding an older (2005) Electra Townie 7D from a frame.
Will be using a 44 tooth single front crank and a 14-34 rear 7 speed Freewheel.
How long must the chain be. Currently the chain is 138 links, bike shifts alright but the chain seems long to me. I'm used to mountain bike chains at 106 links. The foward pedal design of this bike stretches the chain length but I'm not sure how much.
I put a Townie together a few years back, I remember the chain being long, but I don't remember it being THIS long.

theblackbullet

JohnDThompson 

Chain length is a function of both the gearing and the distance from the bottom bracket to the rear axle, so there is no single chain length guaranteed to work in all cases. If you feel the current chain length is not right, @theblackbullet's link to Park's tutorial will help you judge an appropriate length for your chain.

base2 

The Townies have really long chains. It's not just you. Often you can just use 2 regular 6/7/8 speed chains or 1 really long e-bike chain as some come as long as 138 links.

I'm surprised you wore one out. Townie 7d's are usually marketed as a summertime bike & few ever see all that many miles.

I've always felt that the clutch-less derailleurs used on the 7d's were totally inadequate for the weight a length of chain that long. The constant chain slap against the guard would drive me nuts. It would have been a much better design to use a Nexus 7 speed hub & Surly Singulator style chain tensioner instead. Your LBS can rebuild your wheel with the necessary components & do the job for about $350-400 if you feel the constant "slap-clang" detracts from your riding experience.

CNRed

I know the Townie chains are quite long, I just didn't remember it being this long, The last time I had to replace a Townie chain, I remember I had to buy two chains and cut one down. I thought the the total links were about 118 or so. I guess I remembered very wrong.
I didn't wear the chain out, I'm building it from a frame so there was no chain to start with and measure from.
I believe I'll try the Park Tool method a see where that leaves me.
I thiught someone with a 7D Townie might know chain length.

Iride01 

If you have the old chain and you know the bike shifted correctly to every possible gear combo then you can just count the links in the old chain. If you have a oddball chain length requirement for your bike, then you might have to buy two chains and use a piece of the other new chain.

Most bike chains come in 116L which is 116 links. Though I thought I remember seeing some years ago sold in 120L lengths.

Bill Kapaun

Just make sure you have =>1" slack.
Easy to check in situ

SoSmellyAir

Heh, when I read that I imagine someone riding a Townie in cyclocross.

I bought my wife an Electra Loft 7d which similarly has the seat tube set back from the bottom bracket (but by nowhere near the distance in the Townie). The Loft was also available as a 7i version with a Nexus 7 speed hub. But it was more expensive, and I was not sure the hub could withstand her max FTP as she zooms around our community.

shelbyfv

From what I read on BF, Townies are also popular amongst the Super-Sized. Some may live a hard life even if ridden only in Summer.

CNRed

I don't have an old chain, this bike is being built from a bare frame, nothing else, just a frame.
I did figure the chain size out using the Park Tool Large Sprocket method. It seems this bike is happy with 136 links, (pretty long chain). The forward pedal design plus the long wheel base accounts for the length.
Bike is together, rides, shifts and stops excellently, now it;s time to sell it and start another.
Thanks for all the help.