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-   -   DIY chain cover (https://www.bikeforums.net/commuting/1042950-diy-chain-cover.html)

wphamilton 12-27-15 12:41 PM

DIY chain cover
 
12 Attachment(s)
I'm showing in more detail the aluminum strip chain cover from my Dawes SST Review thread. This is amazingly easy to construct with basic tools considering my lack of crafting skills. since this was my first try there are several things that can be improved, or just constructed better by someone with skills. It took me a couple of hours, much of it spent on head-scratching and dull drill bits.

It is a partial chain case, just a strip around the chain to protect my pants and to keep the worst of the elements from the drive train. It works pretty well for that:

http://www.bikeforums.net/attachment...2&d=1451235671

The cover is an aluminum carpet seam strip. It is 1 1/4" wide which is just about perfect IMO, although I think +/- 1/4" would also work. I started with a 10 or 12 foot strip from Home Depot to make fenders with ($14), and had some left over so this was mostly zero cost. I also used a couple of nuts and bolts, a re-purposed reflector mount, some old inner tube rubber, and a few zip ties.

The only difficult challenge is that in attaching to the frame, the positioning needs to be very precise in back, and solid in front. It needs to hang straight vertically without much movement in normal use. I went for the simplest idea.

But first, bending the cover into shape. I just laid it against the chain ring and carefully bent it, using my thumbs to make tiny adjustments where needed. You just look at where it begins to diverge from the curvature and make a little bend at that exact spot. I taped it in place to mark where I wanted to cut it in back.

http://bikeforums.net/attachment.php...hmentid=495301

After trimming the back ends and bending around the cog it's laid over the cog loosely. Notches need to be cut out for the seat stay and rack strut. It looks like a lot of clearance here but by the time this is done it's drawn in quite a bit so it's best to leave an inch of space around the cog. http://bikeforums.net/attachment.php...hmentid=495302 This isn't the best place to join the two sides I think. Doing it over I'd have the break somewhere behind the rack strut, to make it easy to open up and to adjust. With some notches cut out http://bikeforums.net/attachment.php...hmentid=495303 these don't have to be precise because they're going to be padded with rubber.

Next the front mount. It's hard to see here, but it's just a reflector clamp and the guard is clamped tight over the plastic swivel part of it. Large zip-tie through the guard and around the clamp bolt. It's easy to position the chain guard precisely by just moving the clamp around. http://bikeforums.net/attachment.php...hmentid=495304 http://bikeforums.net/attachment.php...hmentid=495305

After getting that solid attach the back. I overlapped the ends, drilled and bolted (while having it off the bike :lol:). Both ends are covered with a piece of inner tube to prevent scratches and rattling, and I put thick rubber in the notches between the struts and stay, and the guard. You'll also see a zip-tie around the stay. Unfortunately that's critical because tightening it there, against the rubber, sets the angle that it hangs at and positioning the bottom at the back: http://bikeforums.net/attachment.php...hmentid=495307 http://bikeforums.net/attachment.php...hmentid=495308

At this point although it should be attached pretty well, it's still wobbly in front and may not be in the right position on bottom, towards the front. The simplest thing to do is brace it from the chain stay. I originally tried it from the drive-side stay, but moved to the non-drive side to make it more solid and easier to work with: http://bikeforums.net/attachment.php...hmentid=495311 http://bikeforums.net/attachment.php...hmentid=495309 http://bikeforums.net/attachment.php...hmentid=495310 Making a clamp from a trimmed-off piece and eyeball it in place for the bends, the critical point is having vertical sides on the clamp part and enough rubber inside to conform, which keeps the clamp rock solid: http://bikeforums.net/attachment.php...hmentid=495312 This part can be improved I'm sure, but doing it this way is very easy and solid, and doesn't look all that conspicuous.

That's all there is to it, simple and effective. I'm hoping this inspires someone to improve on the basic idea. For my part I'm pretty happy as is, but I'm mulling over adding a vinyl cover for a more full enclosure. Maybe someone will take up where I left off here.
http://bikeforums.net/attachment.php...hmentid=495313

BobbyG 12-27-15 01:38 PM

Pretty cool!

fietsbob 12-27-15 02:47 PM

The Nederlanders often have a stretched heavy PVC covering for the sides on their Grand Ma/Pa, classic Old Bike's covered chains .

kickstart 12-27-15 03:18 PM

Huge selection of hard and soft chaincases, covers, mounts, brackets, hardware, and even little mounted brushes.
The largest and most affordable Online Chain Guard Shop!

lost_in_endicot 12-27-15 03:38 PM

That's pretty nice. It probably wouldn't take much more to enclose it if you wanted to. Have you tried it out in the wild yet?

CompleteStreets 12-27-15 04:16 PM

Great job. I'm still waiting for the day when someone can modify the derailleur bike concept so that it includes a full chain case. I have an IGH bike with a full chain case, and the chain doesn't need to be lubed more than once or twice per year. As much as I miss derailleur bikes, it's hard to go back now that I don't have to maintain my chain or crankset and I never have to roll up my pant leg.

wphamilton 12-27-15 04:22 PM


Originally Posted by lost_in_endicot (Post 18417347)
That's pretty nice. It probably wouldn't take much more to enclose it if you wanted to. Have you tried it out in the wild yet?

Sure, I've been commuting with it, with some heavy rain on Wed and Thurs. Also a longer ride in the nice weather yesterday. Since there is no metal touching except for the non-drive side brace there is no rattle. My main concern was with it staying in place but that hasn't been a problem yet.

I've been tempted to add vinyl or Coroplast sides but one thing stops me. I don't really want the extra surface area exposed to side winds, resulting in extra drag. A minor concern I admit, especially for that bike but still enough to stop me from taking the time for it ...

wphamilton 12-27-15 04:26 PM


Originally Posted by CompleteStreets (Post 18417419)
Great job. I'm still waiting for the day when someone can modify the derailleur bike concept so that it includes a full chain case. I have an IGH bike with a full chain case, and the chain doesn't need to be lubed more than once or twice per year. As much as I miss derailleur bikes, it's hard to go back now that I don't have to maintain my chain or crankset and I never have to roll up my pant leg.

Those can be had, but it's ungainly due to the volume described by the various paths that the chain takes, and the gimmicky needed to avoid the front DR.

(they also need to be designed to a tighter tolerance. I tried a proof of concept on my derailleur road bike but it didn't turn out well)

wphamilton 12-27-15 04:33 PM


Originally Posted by kickstart (Post 18417316)
Huge selection of hard and soft chaincases, covers, mounts, brackets, hardware, and even little mounted brushes.
The largest and most affordable Online Chain Guard Shop!

Nice but $38 shipping is a bit prohibitive.

CompleteStreets 12-27-15 04:59 PM


Originally Posted by wphamilton (Post 18417437)
Those can be had, but it's ungainly due to the volume described by the various paths that the chain takes, and the gimmicky needed to avoid the front DR.

(they also need to be designed to a tighter tolerance. I tried a proof of concept on my derailleur road bike but it didn't turn out well)

So, by "those can be had," you mean "those cannot be had." Big, big difference between a chain guard and a fully enclosed chain case. The derailleur bike needs to be revolutionized, or perhaps scrapped in favor of a brand new design. IGH bikes are great but they are heavy and don't operate as well on uphill stretches as derailleur bikes. Maybe one day there will be a bike that has the best of both worlds (great on hills and zero maintenance with no need to roll up pant leg).

kickstart 12-27-15 06:54 PM


Originally Posted by wphamilton (Post 18417450)
Nice but $38 shipping is a bit prohibitive.

Its a flat rate, so I wait and combine purchases. Many items are significantly cheaper there, which often more than makes up for the shipping, plus many items simply aren't available here at any price here.

kickstart 12-27-15 07:09 PM


Originally Posted by CompleteStreets (Post 18417520)
So, by "those can be had," you mean "those cannot be had." Big, big difference between a chain guard and a fully enclosed chain case. The derailleur bike needs to be revolutionized, or perhaps scrapped in favor of a brand new design. IGH bikes are great but they are heavy and don't operate as well on uphill stretches as derailleur bikes. Maybe one day there will be a bike that has the best of both worlds (great on hills and zero maintenance with no need to roll up pant leg).

The Gazelle Friiik has a full chaincase.
https://www.youtube.com/watch?v=9CJ8wPtZHF8

The difference in weight, and efficiency on hills for a standard IGH compared to a derailleur is actually fairly insignificant in actual practice so I don't really see the advantage of the Friiik, but.........

kickstart 12-27-15 07:19 PM


Originally Posted by wphamilton (Post 18417429)
I've been tempted to add vinyl or Coroplast sides but one thing stops me. I don't really want the extra surface area exposed to side winds, resulting in extra drag. A minor concern I admit, especially for that bike but still enough to stop me from taking the time for it ...

I've added a chaincase to a bike that didn't have one, took one off a bike that did, and commute on a bike that has one and a coat guard. Its location and size make any drag or windage far less noticeable than a pannier, tail trunk, or backpack.

wphamilton 12-27-15 07:27 PM

2 Attachment(s)

Originally Posted by kickstart (Post 18417743)
I've added a chaincase to a bike that didn't have one, took one off a bike that did, and commute on a bike that has one and a coat guard. Its location and size make any drag or windage far less noticeable than a pannier, tail trunk, or backpack.

OK Ok I'll try it for a while at least. I can always take it off later if I want.

http://bikeforums.net/attachment.php...hmentid=495383http://bikeforums.net/attachment.php...hmentid=495384

noglider 12-27-15 07:27 PM


Originally Posted by kickstart (Post 18417725)
The Gazelle Friiik has a full chaincase.
https://www.youtube.com/watch?v=9CJ8wPtZHF8

The difference in weight, and efficiency on hills for a standard IGH compared to a derailleur is actually fairly insignificant in actual practice so I don't really see the advantage of the Friiik, but.........

Wow, that's clever.

CompleteStreets 12-27-15 07:31 PM


Originally Posted by kickstart (Post 18417725)
The Gazelle Friiik has a full chaincase.
https://www.youtube.com/watch?v=9CJ8wPtZHF8

The difference in weight, and efficiency on hills for a standard IGH compared to a derailleur is actually fairly insignificant in actual practice so I don't really see the advantage of the Friiik, but.........

I totally disagree. There is a huge difference in the amount of effort required to pedal an IGH up a relatively steep hill when compared to a derailleur bike. I have an IGH bike, so I would know. People on derailleur bikes fly past me on uphill stretches.

The Gazelle Friik you link to is very interesting. It is indeed a derailleur bike with a full chain case. However, it only has one chain ring in the front, so the range of gears is limited. This matters, particularly for steep uphill stretches. Still, nice to see. However, the comments in the youtube video indicate that it was a short-lived bike and is no longer in production. SMH.

wphamilton 12-27-15 07:36 PM


Originally Posted by CompleteStreets (Post 18417520)
So, by "those can be had," you mean "those cannot be had." Big, big difference between a chain guard and a fully enclosed chain case. The derailleur bike needs to be revolutionized, or perhaps scrapped in favor of a brand new design. IGH bikes are great but they are heavy and don't operate as well on uphill stretches as derailleur bikes. Maybe one day there will be a bike that has the best of both worlds (great on hills and zero maintenance with no need to roll up pant leg).

Pretty much. They may be better in person than they look, and certainly better than the one I tried to make, but I can't see slapping a chain case on my road bike. It's a big plus for the internal gear bikes in my opinion. My own issue with internal gear bikes are one, price and two, the extra drag. Not so much the weight of the IG mechanism, although the bikes they come on tend to be heavy. I'll stick with my gears and derailleurs at least for now, and this SS/FG of course.

wphamilton 12-27-15 07:41 PM


Originally Posted by kickstart (Post 18417725)
The Gazelle Friiik has a full chaincase.
https://www.youtube.com/watch?v=9CJ8wPtZHF8

The difference in weight, and efficiency on hills for a standard IGH compared to a derailleur is actually fairly insignificant in actual practice so I don't really see the advantage of the Friiik, but.........

It's pretty awesome, better than my chain-guard. But then I spent about 50 cents and an afternoon on mine, and it does what I want ....

kickstart 12-27-15 07:58 PM


Originally Posted by CompleteStreets (Post 18417777)
I totally disagree. There is a huge difference in the amount of effort required to pedal an IGH up a relatively steep hill when compared to a derailleur bike. I have an IGH bike, so I would know. People on derailleur bikes fly past me on uphill stretches.

I have 2 derailleur bikes, 4 IGH bikes, a mile long 15% grade on my commute home, and I find the difference to be fairly minor, but both of my derailleur bikes are 10 speeds with similar jumps between gears.
From what I've experienced, when others fly past me on hills, its the motor, not the bike that's the real difference.

highrpm 12-28-15 08:58 AM

Pretty neat! What was your motive for a fully covered chain? I assumed it was to either keep winter salt off the chain or to keep your pants cleaner when you ride.

wphamilton 12-28-15 09:34 AM


Originally Posted by highrpm (Post 18418545)
Pretty neat! What was your motive for a fully covered chain? I assumed it was to either keep winter salt off the chain or to keep your pants cleaner when you ride.

For me the main motive for the partial cover is protecting my pants cuffs. One pair of good slacks costs more than a chain cover, even if you buy one with the $38 shipping that kickstart is recommending so it just makes sense to do something. I probably get an aerodynamic boost with the bare metal strip ... not that it matters much with that bike.

For a fully enclosed or partially enclosed case the only rational is protecting the chain and gears as far as I know. Thankfully we don't deal with road salt here, but hard rains can drive grit and mud onto the chain so it's still an attractive goal.

avidone1 12-28-15 09:42 AM

I admire your ingenuity :thumb:

Colorado Kid 12-28-15 06:28 PM

I've tried, Coroplast (To make a fully enclosed chain case.) and it didn't hold up. We get a lot of Snow/Salt and other things that mess-up a chain fast. Has anyone tried something else? Would a VO chain case (modified) work?

wphamilton 12-30-15 11:11 AM


Originally Posted by Colorado Kid (Post 18419928)
I've tried, Coroplast (To make a fully enclosed chain case.) and it didn't hold up. We get a lot of Snow/Salt and other things that mess-up a chain fast. Has anyone tried something else? Would a VO chain case (modified) work?

I had to take the Coroplast side off, as the chain was nicking an inside fastener. I'll have to strap it on outside of the cover strip instead - I'm thinking elastic straps, which would also make it easier to remove and mess with the chain as necessary. Doing that, might as well use vinyl, I think, since you could just stretch it tight.

rmfnla 12-30-15 01:18 PM

First thing we did with our bikes when we were kids was remove the fenders and chain guards.

I see no reason to go backwards... ;)


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