Fizzit's RC freeride build log - now with videos

[fizzit]

This is more of a build log now that I've started getting parts for the build. Below is the original first post and dumb questions etc.

I'm interested in doing LiPo, RC outrunner, CC controller, etc. build as my first ebike build and it would be great if you guys could give me any input on the stuff listed here.

Batteries
44v 10 or 15ah of turnigy lipo

Controller
CC HV110

Motor
HXT 63-74 200kv (the one I'm running in my scooter)

Bike
http://seattle.craigslist.org/skc/bik/1986566005.html
"Schwinn Full Suspension Bike with Front Disc Brake"
Or something like this bike. You get the idea

For the proposed mechanical setup (this is drawing off of a number of builds I've seen here)
The reduction would be:
RC motor (with 11t #25 sprocket already attached) chained to a 50t or so sprocket which would be on a shaft that would be connected to a flange bearing on the same mounting plane as the motor...
And on the other side of the plate/shaft, a 9t bicycle sprocket (#40 chain, right?)

The reduction/motor shebang would be connected by chain to the largest sprocket/chainring on the front cranks.
Would these old freewheeling cranks work?
http://cgi.ebay.com/VINTAGE-SHIMANO-INT ... 1553wt_905
Or would the freewheel be not nearly strong enough?

And then of course the other sprocket/chainring would be chained to the back wheel chainrings. I know I would lose front crank shifting, but would I be able to shift in the back still? Or would the torque cause problems with the derailleur?

The goal of the build would be to have a fun, fairly reliable bike that can go 15-20mi on a charge and 30-40mph max. Oh and hopefully I could keep it under $800

This is all completely theoretical, all I have is the motor and it's still on my scooter So feel free to tell me it won't work at all or something like that. Thanks in advance for any advice!

[spinningmagnets]

Here's a link from the resources thread with some info on how to make a freewheeling crank with new parts that are available off-the-shelf. Perhaps an option?..

http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=7192#p165215

[fizzit]

Thanks for the reply. I've seen that but it looks like the parts would cost up to $100. Is there a particular reason not to use the FFS cranks? Does anyone know if they would fit the bike?

Edit: Also, could someone give their advice on that bike in the craigslist ad? Just from the fact that it has suspension and a disc brake looks good to me, but I don't know if it would be any good, so any opinions from knowledgeable people would be helpful... and also if anyone knows if those cranks will work with it, thanks in advance!

[fizzit]

Well I assume from the lack of replies that everything should work perfectly

I made an offer on the bike and hopefully I can go get it or at least take a look at it this weekend...

[Hillhater]

you may want to review your choice of ESC .
why the HV110 ? and not the HV160 which seems to be the more reliable choice. .. there is only $50 difference.

[fizzit]

That makes sense. Thanks, I'll check it out.

[fizzit]

So I'm pretty much scouring craigslist for cheap full suspension/disc brake bikes, because thats what it seems like would be best, but I don't know much about shopping for bikes, so any advice on what to look for would be appreciated!

Here are a couple examples of what I'm looking at:
http://seattle.craigslist.org/sno/bik/1991388906.html
http://seattle.craigslist.org/est/bik/1994055647.html
http://seattle.craigslist.org/oly/bik/1986647180.html

[AussieJester]

you may want to review your choice of ESC .
why the HV110 ? and not the HV160 which seems to be the more reliable choice. .. there is only $50 difference.

Agreed, for the that $50 you do get a whole lot more controller for your money

KiM

[fizzit]

Thanks, AJ

I made an offer for $150 on this one:
http://seattle.craigslist.org/oly/bik/1995670988.html
It's a "BigHit Grom", looks like a nice bike (retails for like 800) but it might be hard to mount stuff on the frame... is it worth it?

I also offered $75 on this one, they say it's in good condition and it looks fairly solid. (and a big triangle to mount stuff in)
http://seattle.craigslist.org/sno/bik/1991388906.html

And I've been considering this one, one of Mongoose's cheaper bikes...
http://seattle.craigslist.org/sno/bik/1995984080.html

So any advice yet, guys?

[hydro-one]

first one ----Looks good. shit fork. hayes=good brakes. but overall good deal at 150. frames are usually more than that, and i doubt it would break. I would upgrade the fork for sure.......marzocchi is good but that one isnt. check out bikes onwww.mtbr.com that is the best resource for reviews on parts and bikes.

the rest= shit although some might argue

good luck with your build!!!
mike

[fizzit]

Okay, thanks for the input! Sadly the good one sold for 200 and the others haven't gotten back to me.
Now considering this one:
http://seattle.craigslist.org/see/bik/1996555303.html
It looks kinda small though, and doesn't have rear suspension, so I'm gonna call them for more info.

Edit: Well they'll take $80 for the triax one... I really can't decide if I should get it or not.

[fizzit]

I picked up a bike! Thanks to hydro-one for the advice . It's pretty old (11 years) and doesn't have a disc brake, but it's overall pretty solid, and has good reviews on that site (mtbr.com). it's a raleigh m7000 from 1999:
http://www.bikepedia.com/Quickbike/Bike ... &Type=bike

I'll probably replace the fork in the future for better suspension and disc brake. But right now, it'll work. (thats code for i cant afford to replace it ) I've been riding it around for a bit and its really nice-feeling, even motor-less

I was thinking about how to solve the whole shifting thing, because I don't want to ruin the chain/gears by attempting to shift under high torque but I also don't want to blow up my motor by pulling heavy crap and going up big hills on a fixed gear. So I believe I have a solution. The custom RC ESC throttle converter I made has an e-brake input. I can hook this up to reed- or leaf-switches on the shifter (btw, i borrowed this part of the idea from one of liveforphysics posts), and when I press the shifter, it will activate the e-brake, which will temporarily lower the throttle to something like 10%, and during this, the bike should be able to freewheel while the motor drives the chain and shifts easily.

I lowballed $20 on those freewheeling cranks and the offer got accepted, what do you know. They should be here soon as the first actual part of my build Next, maybe some LiPo from the USA warehouse, I can't wait to order it and have it get here in 1-2 days. Or maybe they'll even let me pick it up...

[fizzit]

I have a couple things I have been wondering about that it would be great if someone would chime in on.

First of all, I took my motor out. It's bearing-pulled-out-by-chain-tension condition appears to have worsened:



What I would be inclined to do is mount it rotated so that the chain pulls the bearing back into alignment. Unfortunately, I don't think that will work well, or for long. Are there any alternatives that don't involve replacing the bearing (which costs $$$ i think)?

The other thing is, would it be OK to drill four 1/4" holes into the main support tube that says RALEIGH?


The tube is about 3" tall by 1" wide, so I don't see much problem with that, especially since I'll be bolting a thick piece of aluminum to it that may actually support it. But if anyone thinks that would greatly lower the strength, I would appreciate them saying so

[Hillhater]

does that motor even turn over still ??
At the minimum , i suspect it must have a bent shaft, and possibly damaged bearing seats. you need to strip it down to check the damage.
And , yes, drill away into that frame tube...plenty of strength there, but how will you bolt to it as there is not enough metal to tap into , and a long through bolt will collapse the tube.
You will need to use some rivet nuts (special threaded inserts for "blind" holes in tubing.)
http://www.ullrich.com.au/fastenings/53_nutserts.php

[fizzit]

I'll try to get the motor apart soon to look at it. It does, in fact, still turn. I think I have the same problem as swbluto did with his 63-74, which is why I don't think the shaft is bent, instead the bearing is just messed up (rotated out of the seats, as you said). That and the fact that the motor still revs up fine without vibration.

I didn't think about the tube collapsing Thanks for letting me know about that!

[wildharemtbkr]

Hi sorry to tell you after the fact. The cranks appear to be for an american bottom bracket, the frame has an english one which is smaller and threaded, they will not work. The same seller has some that will fit, but they are cottered cranks and are heavy and weak!! On the plus side your bike is decent, way better then most of the others you were looking at!!

[fizzit]

Darn. Well, thanks for telling me anyways. I knew my n00b-ness would screw me over at some point, but I wasn't expecting it to happen so early

I learned a lot today about cranks and bottom brackets from research that I should have done before. I think I'm still gonna go out and look at or attempt to disassemble the cranks to wrap my head around this whole trials crank/freewheel setup that people are using, because its really confusing to me

The only next step I can think of without having to redesign my drive is to get the Eno 2-speed freewheel and the cyclone cranks. Which adds up to over $150
So obviously, any other ideas appreciated

[Hillhater]

I'll try to get the motor apart soon to look at it. It does, in fact, still turn. I think I have the same problem as swbluto did with his 63-74, which is why I don't think the shaft is bent, instead the bearing is just messed up (rotated out of the seats, as you said). That and the fact that the motor still revs up fine without vibration.!

The bearing is in the stator, and must be still in position or the motor would not turn.
The 4mm bolts fixing the end bell to the stator must have broken or stripped the thread. check carefully.

[fizzit]

I took it all apart, and in fact they were just loose. I suppose I should have checked that
It appears that HXT has not discovered threadlocker yet
Thanks for letting me know about that!

Also, I did more research and found out that those eno dos don't allow two chains. And they're crazy expensive anyways. The freewheel on my scooter appears to use the standard freewheel threading. It has a 5-bolt pattern to attach to the sprocket. So my new plan is to get the cyclone cranks and two big #40 flat machinable sprockets from mcmaster. I will then cut out large holes in each and bolt them onto the freewheel, with some washers to space them from each other to prevent chain interference.

What would be really cool (read: cheap) though is if I could take 2 of the sprockets off of the spider on the bike and get some sort of adapter to attach them to the freewheel. Then I wouldn't even need to buy sprockets. So I am currently hunting for an adapter for that

Edit: hmm never mind the fw uses 4 bolts. Which is really annoying because the cool sickbikeparts chainrings I just found use 5 bolts

[fizzit]

Slight update. I got a bunch of stuff in the mail. These are a couple of problems/things I'm working on currently, just putting them out there for the record and in case anyone has any ideas.

A) freewheel on my scooter is stuck
I placed the remover on the freewheel and clamped it in a 12" or so wrench and then clamped the scooter wheel vertically in my vice (so it was actually clamping on the tire, with soft rubber shoes on the jaws of course) and pounded pretty dang hard on the end of the wrench with a mallet. The wheel just started turning. The problem is, I don't think I have a stronger way to clamp the wheel than the vice (which turned also).

B) bicycle chain is not #40 chain
Yeah I'm an idiot. My 11t #40 .5" bore sprocket's teeth are way too wide, I immediately discovered. I started grinding on them with my dremel to thin them down to the right width, and it's taking forever, but I think it might work! I'm also trying to make a sprocket out of sheet steel that I can just attach to the old one, but lets just say it's not pretty

And thats it, only two problems so far, thats surprising with my level of incompetence

[recumpence]

Fizzit,

Please do not get discouraged. You are going through the typical groing pains. This is still a relatively rare/exotic hobby.

#40 sprocket will work fine if narrowed. I have one on my work bench right now that I am setting up the same way. However, in my case, I am using a large grinder while spinning the sprocket on the lathe to narrow it.

You are actually doing quite well considering you jumped into the deep end of the pool!

Matt

[fizzit]

Thanks, recumpence
I'm pretty sure I'll run out of money way before I get discouraged, as it stands I'm deciding whether I want a bike with a controller or with batteries Time to start ebaying random crap I have laying around!

Thats good that thinning the sprocket works. I might have to get another and redo it, when I started I didn't think it over too well and didn't mark the teeth so they arent in the best line

Also, in other news, I got the freewheel off with some help from google. My new problem is that the freewheel threads halfway onto the cranks, and then starts to resist threading on. From the appearance of the threads, it looks like the freewheel started shaving off the threads on the cranks. I thought all freewheel threads were 24 tpi? Oh well, I don't plan on pedaling too much, maybe it'll work fine threaded only halfway on

[AussieJester]

I am using a large grinder while spinning the sprocket on the lathe to narrow it.

ah ba ya whaaat!?! Recumpence goes "ghetto" well i never

Time to start ebaying random crap I have laying around!

I am sorry to be the one to tell you fizzit, but you are showing all the signs of e-bike addiction :: nods head::
Soon you will buying e-bike components instead of food, which is, incidentally ...the real reason behind weight lose in e-bike owners ;-P

Seriously best of luck with the build and as Matt says it is "its still a relatively rare/exotic hobby." and
you have dived straight in, kudos to you and best of luck with getting it all together

KiM

[fizzit]

I am using a large grinder while spinning the sprocket on the lathe to narrow it.

ah ba ya whaaat!?! Recumpence goes "ghetto" well i never

Time to start ebaying random crap I have laying around!

I am sorry to be the one to tell you fizzit, but you are showing all the signs of e-bike addiction :: nods head::
Soon you will buying e-bike components instead of food, which is, incidentally ...the real reason behind weight lose in e-bike owners ;-P

Seriously best of luck with the build and as Matt says it is "its still a relatively rare/exotic hobby." and
you have dived straight in, kudos to you and best of luck with getting it all together

KiM

Hmmm would this "addiction" also be characterized by attempting to convince one's parents to convert one's "College fund" to an "ebike fund"? Because I would never do that.
Thanks AJ, doing this is already a lot of fun.
BTW, your work is amazing, I can only dream of someday making an e-bike 1/50th as cool as yours


Stuff I've done:
I ordered the sickbikeparts freewheel, it literally shipped half an hour later, and because I live in the same state as them, it shouldn't take too long to arrive
This is my wooden mockup that I made of the reduction layout while waiting for my ebay aluminum to come.




As you can see, about the complexity and beauty of a cardboard box, but lets hope that somehow it doesn't explode. I'll be sure to take video.

And here, hopefully you can see how it's all going to work out. I haven't replaced the cranks yet, but I managed to convince the guy that lives across the street from my friend to let me use his crank remover this weekend. Probably should have asked for a bb-tool also if I'm gonna use my extended spindle...



The layout marked on my shiny new 16"x8"x3/8" block of 6061


Any comments, criticism, or insults are appreciated, but extra-appreciated if they are soon because I hope to start working on the aluminum tomorrow!

[dequinox]

Hi fizzit, you're using some seriously heavy plate there for a motor mount! Are you going to sandwich it around the tubing or are you going to just let it hang from one side (sorry doing homework and don't have time to look through the whole thread on my short break from it)? I recommend thinner plate and a sandwiching configuration that hangs below. It would be a little lighter I think. You could always drill a bunch of the weight out also. Take any large swath of the plate you don't need and drill a large pattern of holes in a rectangle so that it falls out...or if you have a jigsaw you can just drill 4 large holes (large enough to fit the blade) at the corners and get-a-cuttin'.

If you want to take a look, my build used a sandwich-style motor mount: http://endless-sphere.com/forums/viewto ... =6&t=14038

I'm a total dork in the videos...you'll get the idea if you just see the first few seconds of the first vid.