Need Advice on Converting 1985 Mountain Bike

[bdc43]

Greetings!

Well, after much "lurking", I finally decided to take the plunge and join the forum. I've been interested in electric bikes for about a year now and have been doing quite a bit of research online (not to mention watching all the Doctor Bass videos I could find on Youtube! :lol: ) Seeing as the hands on approach is the best way of learning, I would like to do a conversion myself. I have an old 1985 CCM Brutus 6-speed mountain bike that I haven't ridden in about 16 years due to knee problems. I don't have it with me yet, it's still stored in a shed up at my parents' place, but last time I was visiting I took the following measurements to see if a hub motor kit might fit:

Distance between rear dropouts: 5 1/4 "

" " front " : 3 3/4 "


Rims: 23"

I didn't do the "magnet test" so I can't say for sure if the forks are steel or aluminum.

I will probably have to doublecheck these measurements, espcially for the rims, since I can't remember if I measured the inside or outside diameter (like I said, I'm a complete newbie).

Anyway, to give you a better idea of what I have to work with here are some pics of the bike:

(NOTE: In my excitement and haste, I had initially posted these pics to the "E-Vehicles General Discussion" section of the forum under a new thread I titled "Another Total Newbie", instead of here. I asked the Forum Moderator to move the thread here if necessary. Sorry in advance for any duplication of info between the two sections.):


IMG]http://i838.photobucket.com/albums/zz308/bchamb1967/bicycle007.jpg[/IMG]

There doesn't seem to be much rust , if any on the bike, although it's kind of hard to tell under all that dirt and grime.The tires appear to have a bit of rot (as you can tell from the bottom sidewalls in some of the pics) but no bid deal since I would be switching the offroads to a good set of street treads. I should also mention that the cable runnin to the front up is connected to an old mechanical speedometer I bought at Canadian Tire back in the late 80s. The "fannypack" hanging from the handlebars is an "emergency toolkit", also from Canadian Tire (from the style and color, you can probably tell it also was purchased sometime in the late 80s, early 90s. :lol: )

Thanks in advance for any tips/advice!

 

[dogman dan]

Solid old school mtb. I have a fuji just like it. I had a problem with the dropouts when I put a front hub on it, so I'd advise a torque arm if you do a front hub. On mine, the drops were an alloy that bended pretty easy, and I'd not tightened the nuts that good. If you want to improve the brakes, you could put v brakes on the same brake bosses. I never liked the canti's on old school mtb's, the cheap v brakes on a wall mart bike grab better.

If you live in Canada, then you know who to shop with, ebikes-ca.

 

[dingoEsride]

I've got an old rigid like this one which I was thinking of electrifying but the old cantilever brakes and heavy frame put me off a bit but changing these and forks with shokers would give it a revamp and braking is very important,
ps love the old speedo

 

[mrzed]

Those brakes might just be the best thing on that bike. The are cheap copies of old French Mafac cantis, and properly set up with good pads, they are surprisingly strong. The levers would have to go though, and it is still true that v brakes will be stronger, so may as well replace the whole set. But that begs the question is the bike worth it?

Yes, the forks and the entire bike is steel, but cheap steel. It would be a usable ebike donor, But I would suggest if you are putting a few hundred dollars minimum into e-gear, a 150-200 dollar craigslist deal would be a better bet. Something in a mid range older mountain bike is an ideal starter.

 

[EVTodd]

I have an old school Blue Max mountain bike (actually the first mountain bike I ever owned, just got it back from a friend) that I've been playing with lately. Canti brakes are just fine if you find some nice pads for them. I can't remember the brand but I got some off eBay and it stops great now.

I'm seeing a lot of this style frame around here converted to single speed. I personally just added a few modern parts to mine like a 1 1/8" stem adapter and stem, a nice seat, a new chain, and new tires. It's retro-cool now! 8) I would electrify it in a second but I feel like I should keep at least one bike for "normal" riding. Well, maybe another friction drive with a small battery for the one big hill I have almost every day.

I really like the Vector style handlebars on your bike and the Comp III tires (too bad they're probably too old to use).

I say use it if it's still solid, just lube everything up, check all the bearings, put new tubes and tires on, and have fun.

 

[Zoot Katz]

Nice big triangle for batteries and a fairly long wheel base.
I have a '85 Norco Sasquatch frame that I'd converted to a city bike and rode daily for six years.
Great geometry, butted Cro-Mo tubing, brazed lugs and forged dropouts made it worth while building up.
The original crank was nice too.

The drop outs on that bike look like they're stamped.
I'd not trust stamped drop outs or fork ends with a hub motor.

 

[amberwolf]

I have an old 1985 CCM Brutus 6-speed mountain bike

Bike itself looks good. It's all steel for frame and forks and bars. I have had several bikes very similar to it from the 70s and 80s. It's probably not *great* steel, though, so as other said, use torque arms, and I'd recommend a rear rather than front hub for that frame.

If it's like all of the ones I had, it's 26" tires, but 23" rims probably means 24" tires. They'll be labelled on the tires themselves, molded into the rubber. If those are 160mm cranks then the tires by comparison probably are 24".

Don't use that aluminum Swiss rack for anything heavy, or batteries though--the dropout-rack braces will shear off at the rack end, right at the rivet. Ask me how I know. Nice rack for regular stuff, though. Also don't bend the spring-loaded clamp farther back than vertical; it'll probably pop the springs out the bottom and it's HELL putting them back.

There doesn't seem to be much rust , if any on the bike, although it's kind of hard to tell under all that dirt and grime.

There will be some rust in places you can't see, like inside the tubing and stuff, especially near the dropouts where the welding ventholes are, but it doesn't usually affect it's performance.

I'd pull the shifter and especially the brake cables out of the sheathing, though, and check for rust. If there is any, replace the cables at the least, and preferably the sheathing too (though you can just oil the sheathing if it's not dry-rotted on the plastic part outside). Rusty cables can snap--even one broken strand on your brake cable can reduce your braking force on the cable by HALF. Bad juju if it happens when you need it most. Again, ask me how I know.

Same thing goes for the cable sheathing--if the plastic looks even vaguely crackly, replace them. Otherwise when you slam on the brakes all the force the sheathing is there to transfer along it's length may push outward just a little too hard and BAM the plastic goes away, and the metal coils or parallel strands of the sheathing are no longer bound together, and you have zero braking because no force is tranferred from your lever to the arms. Don't bother asking how I know, you probably figured it out by now.

 

[dogman dan]

I think the problem with canti brakes on bikes I've had was shitty cable routing. Wierd little tubes brazed to the bike that have s curves in em causing buku friction. Replace with straight runs of cable to v brakes and Viola! Always the problem is with the rear brake, the fronts work fine. V brakes just have a longer lever, so even cheapies get good pressure. On my ol mongoose wallbike, 5000 miles of riding has caused the frame to weaken, and now when I put on rear brakes, you see the frame flexing. That's how strong a cheap v brake can be.

If you want to replace that front fork, look at surly ones. Beefy. That bike will need 1" head tube forks.

 

[bdc43]

Thanks for all the great advice, everyone. I guess my challenge now will be to figure out, budget wise, if the extra cost of upgrading a 25 year old bike won't be too prohibitive given the fact that the electric conversion itself won't be cheap.

Mrzed, when you mentioned the "cheap steel" aspect of my bike ( I figured as much, since it was made in Taiwan),were you implying that would be risking my personal safety if I did a conversion with this bike ? I realize the extra weight of the hub motor, batteries, etc. would put quite a bit of strain on the frame, not to mention the rear forks (I would prefer going with a rear end conversion for better hill climbing ability). I wonder if anyone here on this forum has had the unfortunate experience of having some portion of their bike frame (tube, forks, etc.) let go after having done a conversion on an older, cheap model bike? I don't wnat to sound paranoid, but I wouldn't want to go through all the expense and trouble of an e-bike conversion only to go "flying" over the handlebars because a part of the frame lets go due to corrosion and/or metal fatigue. On the flip side, I kind of still have a bit of nostalgic attachment to this bike and it would be nice if I could give it a new lease on life as an e-bike. Would be kind of sad to see the old girl chopped up for scrap.

 

[amberwolf]

Thanks for all the great advice, everyone. I guess my challenge now will be to figure out, budget wise, if the extra cost of upgrading a 25 year old bike won't be too prohibitive given the fact that the electric conversion itself won't be cheap.

You could convert it just as it is right now, just replacing the tires/tubes and brake pads, oil/grease everything up, and it'd be ok. There's just stuff that would be *better* if you upgraded it. Only thing I don't think will work well is if you try to use that rack for a battery rack. I think it will break as I described. Oh, and the cables need to be checked, just in case.

Mrzed, when you mentioned the "cheap steel" aspect of my bike ( I figured as much, since it was made in Taiwan),were you implying that would be risking my personal safety if I did a conversion with this bike ?

I doubt it. It's just that the steel it's made of is heavier and softer than a good cromoly (Chrome/Moly, ChroMo, cromo, etc.) frame would be. The front dropouts probably aren't really up to the task of holding a >350W hub motor in, but with really good torque arms probably could do it anyway. Using a rear motor would be a better idea, though, also with good torque arms.

I wonder if anyone here on this forum has had the unfortunate experience of having some portion of their bike frame (tube, forks, etc.) let go after having done a conversion on an older, cheap model bike?

I'd be willing to bet that most of the failures experienced have had more to do with inexpert mounting or faulty torque arms (or *no* torque arms), than most anything else. I'd be willing to bet a good lunch that the welds, steel, and general QC on that bike are better than those on modern cheap wallyworld bikes, based on the ones I get from people for my projects.

Just do a check for rust or cracked welds, neither of which is all that likely, if the chain isn't rusted solid. Unless it was left out in the weather for years, or ridden on salted roads and left unwashed, it's probably fine.

I built the extremely heavy (>150lbs) CrazyBike2 out of junk bikes and *it* hasn't broken on me yet, except for stuff I did to it in the process of modifying it in what turned out to be stupid ways. :lol:

 

[Drunkskunk]

Looks like a perfect bike for a conversion to me. Tires, tubes, and elbow grease are all it appears to need.
Cool retro Speedo too.

A true 26" bike tire is measured as the standing height of the tire on the rim, nothing like a car tire. It has a rim size 22 inches across.(559 milimeters) It should say 26X1.75 or something close to that onthe tire which is what most modern bikes use, and most old mountian bikes. If it gives the tire size as a fraction (26X1-3/4) then it won't be the same size rim and finding tires that fit may be a problem.

A front motor would probably need a diffrent front fork for the reasons stated above, but a rear motor should be fine.
I wouldn't mount the batteries on a rack in the back with that bike, though. (1) the seat tube leans farther back than normal so your weight would be further back. (2) you have all that amazing space in the triangle, it would be ashame not to take advantage of it.

 

[mrzed]

Mrzed, when you mentioned the "cheap steel" aspect of my bike ( I figured as much, since it was made in Taiwan),were you implying that would be risking my personal safety if I did a conversion with this bike ?

I doubt it. It's just that the steel it's made of is heavier and softer than a good cromoly (Chrome/Moly, ChroMo, cromo, etc.) frame would be. The front dropouts probably aren't really up to the task of holding a >350W hub motor in, but with really good torque arms probably could do it anyway. Using a rear motor would be a better idea, though, also with good torque arms.

It is not the "heavier" part I would worry about, but specifically the "softer". Cromoly steel being so much harder than the cheap steel on these bikes helps a lot.

I've seen bikes of this sort fail (when abused of course, taken over jumps or ridden on rough trails). I agree though, that you would not likely be risking your safety with a rear hubmotor. Front on the other hand would scare me with that fork. It also depends on how much power you plan to run through it - for a standard 36v/20a system, you'll probably be OK.

How handy are you with bikes? I would recommend at minimum for that bike:

- New brake pads front and rear (~20$)
- New (used) brake levers (Those things are plastic and flex WAY too much for good braking (~5-15$)
- New brake cables (~5-15$) (why risk having the front snap on you?)

Possible replacements include:

- New shift cables (~5-15$)
- new housing for brake/shift ($10-20$)
- repack bottom bracket and hubs if you know how to do it (cost of grease)
- tires and tubes (5-80$)

Because you already have the bike, it may be worth it. Depends on how much it totals up to. My personal fave for ebike conversion would be a mid to high end late 90's - early 2000's mountain bike with a steel frame. These are often sold on cragslist for very reasonable prices. They also have the advantage of better handling at speed than most of the cheap bikes. That flex in the cheap frames is even more noticable with 30-40 lbs of ebike gear at 30+ kph.

That said, you already have the bike, and the ebike gear cost will be the same either way. No reason not to put the thing back on the road. If you find it is not holding up, or just want something better later, there is no reason you can't get a nicer bike later and transfer the gear.

 

[bdc43]

Well, after a lot of hesitation (and confusion...LOL), I finally went with my original bike. Although I had to replace a few things to make it roadworthy (tires, chain, better seat, brake pads and hubs....bearings were shot) which probably cost me more than what I paid for the bike when it was new, the fact that it has a near bulletproof steel frame won me over. I went with a rear 9C kit from Ebikes.ca (ordered through Ypedal) and a 48V lithium-polymer pack (Zippy Flightmax). I put over 217km on it last year and the bike performed flawlessly. The torque on this 9C motor never ceases to amaze me , especially since I'm a pretty big guy at 5'11" and 241lbs (not all muscle....lol) and it hauls me along like I weighed nothing! Max speed I've reached is about 43 km/h. If you want to see pics of my conversion, head over to the "E-Bikes Photos & Video" thread.

 

[bdc43]

Mrzed,

You had suggested replacing the plastic brake levers due to flexing but I checked them with a magnet and it turns out they have a metal core. The only braking problem I have encountered so far is because of the extra weight of the conversion, I'm constantly having to adjust the brake tension after every ride. That, plus I get this annoying squealing sound from my front pads on braking. I tried cleaning the rim with alcohol but the squealing persists. I might try sanding the pads a bit ( I was advised that might solve the problem).

 

[ddk]

... That, plus I get this annoying squealing sound from my front pads on braking. I tried cleaning the rim with alcohol but the squealing persists. I might try sanding the pads a bit ( I was advised that might solve the problem).

I love my squealing brakes.
They're like a bike bell, on steroids.

 

[MikeFairbanks]

Those front forks are steel.


That's an easy bike to convert whether you go rear wheel or front wheel.


Either will work fine.


Mine is similar.

 

[Ykick]

That, plus I get this annoying squealing sound from my front pads on braking. I tried cleaning the rim with alcohol but the squealing persists. I might try sanding the pads a bit ( I was advised that might solve the problem).

Sometimes the only relief for squealing rim brakes is add toe-in/out to the pads.

 

[bdc43]

@MIkeFairbanks,

I agree, the conversion went pretty well on this old bike....the only exception being spreading the forks to get the hub/wheel assembly into the rear drop outs: boy, were my shoulders sore after I finally got it in ! :lol: Haven't gotten the bike out yet this season due to a bent crank arm I'm trying to find a replacement for. It's 165mm square tapered. If anybody on the forums has a junked bike that still has good square tapered crank arms of similar or close enough size, I'm willing to take them off their hands ! :lol:

 

[bdc43]

Wel, believe it or not, I finally found a crankset for my old timer, courtesy of my frindly neighborhood bike shop. They're a little shorter than the originals, something like 160mm instead of 165, but I think they'll do the job. I just hope my bottom bracket is till holding up....with all the trouble I went through to find a crankset, I can just imagine the hoops I'll have to jump through just to find a bottom bracket!