HS3540 freewheel removal/tear down to 5spd

[crusoe]

Hey guys I'm having some chainline issues causing this http://imgur.com/9Qjxn

I've taken a look at the freewheel that comes stock with the HS3540 from ebikes.ca, and it looks to be threaded type? (need chain whip). Anyway, I need to tear this freewheel down to a 4 or 5 speed to fix my chainline issues. Do I need a special tool to take apart the freewheel once it's off the axle?

Do these spacers look like they'll work?: http://www.amazon.com/gp/product/B001CJVLWO/ref=ox_sc_act_title_3?ie=UTF8&m=A2TE9IQP68MWQU

[biohazardman]

Yes a threaded freewheel fits on the 3540 not a cassette. You don't have to use all the gears. Would you be able to just adjust your derailleur to keep the chain line in acceptable limits using fewer gears? Don't forget to grease or use antisieze on the threads when you install the freewheel so you can get it back off if you ever need to. If you put the freewheel on and ride it you will need a special tool to get it back off as well. There are also special tools to tear down the freewheels if needed.

[crusoe]

My bad, just learned the difference. I have adjusted the derailleur already, as a temporary fix, but I want to be able to pedal at speed so I wanted to get rid of some of the largest cogs.

Is it the, FR1 or FR4 that I need? http://www.ebay.com/itm/Park-Freewheel-Removal-Tool-FR-1-/230643478674?pt=LH_DefaultDomain_0&hash=item35b36c3092#ht_649wt_874

I've read to take apart the freewheel itself, all you need is two chain whips? source http://sheldonbrown.com/freewheels.html

[crusoe]

I found Doctorbass's semi related thread http://endless-sphere.com/forums/viewtopic.php?f=2&t=27108&hilit=freewheel

The problem is, I don't think I can cut off the largest cog area (as seen in the fifth picture above) because that's where the threading is actually attached to the motor.

Hmm, will one of these maybe work? http://www.amazon.com/Sprocket-Wheel-Freewheel-Scooter-Bicycle/dp/B0053WWHK6/ref=sr_1_1?ie=UTF8&qid=1336104068&sr=8-1

[Chalo]

I found Doctorbass's semi related thread http://endless-sphere.com/forums/viewtopic.php?f=2&t=27108&hilit=freewheel

The problem is, I don't think I can cut off the largest cog area (as seen in the fifth picture above) because that's where the threading is actually attached to the motor.

No, you can't cut off the threaded end. Cutting either end shorter is a terrible idea all the way around. I don't think Dr. B's glued-up freewheel will stay together very long in use. There's a reason both freewheel sprockets and cassette sprockets are screwed on tight, and not just held lightly with a snap ring or circlip.

Hmm, will one of these maybe work? http://www.amazon.com/Sprocket-Wheel-Freewheel-Scooter-Bicycle/dp/B0053WWHK6/ref=sr_1_1?ie=UTF8&qid=1336104068&sr=8-1

Most 3- and 4-speed freewheels fit on the same 1-3/8"-24 threads that ordinary 5-, 6-, and 7-speed freewheels use. That one looks like it does.

Note that all the 3-, 4- and 5-speed freewheels I have ever seen feature a 14t small sprocket. That does not yield a very high top speed with normal sized chainrings (although it's more mechanically efficient and way more durable than an 11t small sprocket).

Chalo

[Chalo]

Hey guys I'm having some chainline issues causing this http://imgur.com/9Qjxn

That looks like you have too small a chainring placed too far out from the bottom bracket shell. What size ring are you using, and what length BB spindle?

It's quite normal in this time of 9, 10, 11-speed cassettes to have the chain almost touch the inside of the dropout when it's on the outmost rear sprocket. So there's something weird about your bike-- probably several somethings-- that lead to the mechanical interference you have.

Chalo

[crusoe]

That's what I'm thinking too. I'm running a 100mm BB and a 38t front chain ring. I'm also running an e13 srs chain guide (2004 model) that probably adds some mm's offset. There are also two black plastic spacers, between the BB cup and the BB itself (one on drive and one on non drive).

I just ordered a 42t front ring, so hopefully that will lift the chain, and in combination with that three speed freewheel, I'm hoping to solve the problem. It's a shame I haven't been able to find any 11t - XX type freewheels, because the 14tooth is pretty useless, as you've mentioned

[Chalo]

That's what I'm thinking too. I'm running a 100mm BB and a 38t front chain ring. I'm also running an e13 srs chain guide (2004 model) that probably adds some mm's offset. There are also two black plastic spacers, between the BB cup and the BB itself (one on drive and one on non drive).

Is the ring going to rub on something if you offset it inward? You can use long chainring bolts and chainring/axle spacers to overhang the ring to the inside of the crank. I've done this before and it doesn't hurt anything.

Whatever front and rear gearing you have, the goal is usually to set it up so that the middle plane of the chainrings lines up with the middle plane of the sprocket stack. If you have odd numbers of rings or sprockets, then these middle planes correspond to actual sprockets, and if you have even numbers, they correspond to the central gap.

I just ordered a 42t front ring, so hopefully that will lift the chain, and in combination with that three speed freewheel, I'm hoping to solve the problem. It's a shame I haven't been able to find any 11t - XX type freewheels, because the 14tooth is pretty useless, as you've mentioned

Even 42t is pretty small for an assisted bike, though it would be OK as an inner ring of a double. Rings up to 56t are available without too much trouble or expense, in 110mm x 5 and 130mm x 5 bolt patterns at least. If you have a 56t ring, then using a 14t small sprocket still yields a pretty tall ratio.

Chalo

[crusoe]

I'll have to play around with all the spacing and washers once I get everything in hand, but thanks for all of the tips!

Do you know which of the FR series removal tool I'll need to remove the freewheel from the HS hub? FR1, FR2, FR5? Thanks!

[nicobie]

Justin at ebikes.ca has the one you need.

[Sacman]

That's what I'm thinking too. I'm running a 100mm BB and a 38t front chain ring. I'm also running an e13 srs chain guide (2004 model) that probably adds some mm's offset. There are also two black plastic spacers, between the BB cup and the BB itself (one on drive and one on non drive).

I just ordered a 42t front ring, so hopefully that will lift the chain, and in combination with that three speed freewheel, I'm hoping to solve the problem. It's a shame I haven't been able to find any 11t - XX type freewheels, because the 14tooth is pretty useless, as you've mentioned

Crusoe,
If you're wanting to pedal at speed and the 42t front chainring is the largest you can go before your chainstays start to interfere, there is another (more expensive) solution. Look at Schlumpf High Speed Drive or Hammerschmidt. These are just 2 examples of geared cranksets which effectively muliplies the size of your front chainring. The Hammerschmidt multiplies by 1.6 and the Schlumpf multiplies by 2.5.

[Sacman]

Most 3- and 4-speed freewheels fit on the same 1-3/8"-24 threads that ordinary 5-, 6-, and 7-speed freewheels use. That one looks like it does.

Note that all the 3-, 4- and 5-speed freewheels I have ever seen feature a 14t small sprocket. That does not yield a very high top speed with normal sized chainrings

Another problem with the 3 and 4-speeds freewheels (I saw the other day on Sheldon Brown's). The spacing between the sprockets of the 3 and 4-speeds are greater than the spacing between the 5,6 and 7-speeds freewheels... which makes for not smooth shifting if you're still using the shift levers for a 5, 6 or 7-speed.

[crusoe]

I was planning on using the 9speed shifter I currently have. As the bike stands now, I can dial out the top two largest sprockets and the bottom two lowest sprockets on the 7speed HS3540 stock freewheel. So that leaves me with three gears.

In regards to cog spacing, I was reading that also, but I'm going to just take my chances - it only costs $10 bucks for the 3spd, and free shipping from hong kong! I'm not too concerned about smooth shifting either, to be honest. I don't do much shifting to begin with. Usually smallest cog on road and most offroad, until I get into the super tight, technical single track, then I'll switch into the 20t so I can add some low end torque in places.

[Chalo]

Another problem with the 3 and 4-speeds freewheels (I saw the other day on Sheldon Brown's). The spacing between the sprockets of the 3 and 4-speeds are greater than the spacing between the 5,6 and 7-speeds freewheels... which makes for not smooth shifting if you're still using the shift levers for a 5, 6 or 7-speed.

Index shifting is not the only way to shift. Friction shifters don't care what your sprocket spacing is.

Index shifting came along during the days of 6 and 7-speed gearing, and it was retrofitted to 5-speed systems to serve the cheapest new bikes. But before those standards were settled upon, sprocket spacing was not uniform among all freewheels with the same gear count. That means all 3 and 4-speed, most 5-speed, some 6-speed and a few 7-speed freewheels were never intended to index and can vary quite a bit between different examples. So with those, you just don't use an index shifter.

I recently set up a utility bike for my wife, with a symmetrical rear wheel that only had enough room for a narrow 5-speed Suntour freewheel. By trial and error, I was able to determine that it would index reliably with a Shimano 6-speed index shifter and a modern Shimano derailleur. But that was just dumb luck.

Chalo

[dogman]

For sure, once you get to fooling around with it very much, you want to just go to old school shifters. They allow you to fine tune the alignment of not only the rear derailur, but also the front one, if needed for a whacky chain angle.

You'll end up just setting it up for high gear, and leaving it there anyway. So nice shifting will matter a lot less.

[crusoe]

Update: just purchased the freewheel removal tool from ebikes.ca. I'm in Canada so it should be here soon!Thanks for the tip Nicobie

In regards to friction vs indexed: All very good points brought up. I'm probably going to try to get the 9spd indexed shifter I have now working first.
I know the spacing between the sprockets is different between 3spd and 7spd freewheels, but shouldn't the 9spd shifter still work? Maybe just take one or two clicks to get it to switch gears? Though, if the indexed route fails, I'll definitely go the friction route.

[Chalo]

In regards to friction vs indexed: All very good points brought up. I'm probably going to try to get the 9spd indexed shifter I have now working first.
I know the spacing between the sprockets is different between 3spd and 7spd freewheels, but shouldn't the 9spd shifter still work? Maybe just take one or two clicks to get it to switch gears?

7-speed is usually 5mm between sprockets, 9-speed is 4.34mm. 3-speed is most likely somewhere in the range of 5.3 to 6.3mm. So, one click probably won't do it and two definitely won't. I'm curious to see what your actual results are, though.

Chalo

[crusoe]

I will keep you updated. Just wondering why two clicks definitely wouldn't do it? Isn't the throw of two clicks 4.34x2 = 8.68mm ?

[Chalo]

I will keep you updated. Just wondering why two clicks definitely wouldn't do it? Isn't the throw of two clicks 4.34x2 = 8.68mm ?

That's right, 8.7 is not equal to 6 (or whatever spacing the 3sp freewheel has). I suppose you could use it more or less like a front triple, where the inner and outer sprockets are governed by the derailleur limits, and the center sprocket is governed by the middle click out of five usable clicks. Sounds hokey to me, but it might work. Most inner limit screws on modern derailleurs won't do up that far to the right, though.

Anyway, the cure is simple and cheap, if one is needed.
http://www.amazon.com/Pyramid-Thumb-Shifter-Right-Black/dp/B000AO5JTS

[crusoe]

Here is the final update:

1. the 3 speed I bought from Hong Kong was nearly as wide as the original 7 speed cluster - confirmed Chalo's advice
2. the 9 speed indexed shifter did not work to shift gears at all - confirmed Chalo's advice
3. in order to avoid chain rub completely I've had to go back to the single speed, 16t in the rear 42t up front. It seems pretty useless at anything over 25km/h, but it may help, who knows!