Honda CBR600F2 conversion
 

Picked up the cbr today. Thinking of renaming my cat Peter Fonda:D. Its a '94 with just under 25k miles on the clock. Some damage to the right side fairing as it had been stolen at one stage.

Plan is to use 2 nissan 48v forklift traction motors for series - parallel setup. Minimum of 72v possibly go to 96. Controller will be my own custom igbt version of the open revolt. Not sure about the charger but the petrol tank is plenty big to accomodate a low power version of the open source charger by Simon Rafferty.

Batteries will either be Odyssey pc680 agms or headway 16ah. Thats the basic plan anyway. Now i've never even sat on much less owned a bike until today so like in that film wild hogs its a case of "all the gear , no idea!":thumbup:


So first question. Can someone please tell me how to put this thing on its center stand ?? :D:D

I took the motors to a local engineering works last week and had the coms turned and the splined shafts turned down to 19mm. Saturday morning I set about milling a 6mm keyway into the shafts. Nightmare job. The shafts are glass hard:mad:. Got there in the end so i'm into scraping out the com segments and replacing the brushes.

Stomp on the "lever" for the centerstand while lifting at the passenger footpeg... Not hard, just need the right technique... And once you have figured it out, remove that junk... It's just useless weight that you lug around... The only practical use I ever found for mine is to make cool sparks in the corners...;)

There's always some sort of tail grab on the bike... you don't need to stomp on the center stand at all.

Put your right foot on the center stand pad, and the bike will balance itself on the center stand. Lift up and pull slightly back on the left clip-on bar, and the bike will easily lift up on the stand.

When I was 100lbs or so, I was doing this with a 600lb bike loaded with gear. It takes nothing but technique.

Ok, so "stomp" might not be the right exact word... How about "put distinct pressure on" ?! Like I said and you, doesn't need much pressure, just technique...

I wasn't being contradictory, just making it more clear what I thought you intended to say. When you tell someone to "stomp" on something, I can see a newb who doesn't know any better literally stomping on the pedal thing, and probably dropping the bike over on it's side.

I've seen it happen plenty of times... :thumbup:

Well got her on the stand. A biker friend called in this evening and found the stand had broken and been rewelded incorrectly at some point. Some gentle adjustment with a crowbar got it working perfect. That said it take a good bit of energy to get it on the stand. Perhaps that why a lot of bikers are big and hairy :):)

Really, it shouldn't take much effort to get it up on there. I mean, seriously - When I was small, I could still put fairly large bikes up on the centers.

The effort required may have been due to the "ruined" center stand.

I agree, it should be fairly effortless since that bike is pretty light... Trust me, it's another thing with a big bike...;)

You mean like a GL1800? Nah, still pretty easy, I think. Granted, significantly more difficult, but still fairly easy. The whole process of mounting the center stand is leverage, so by definition, it shouldn't be difficult.

Started the teardown. Nothing really exciting but i was bored so figured i'd do a few videos:
http://www.youtube.com/watch?v=HV9QZD7zP3w
http://www.youtube.com/watch?v=X-SHkNieR20

I've always wanted an electric motorbike. Can you take video of the process of mounting the motors? I've never really been sure about how to do that.

I'll be videoing the whole process with luck! Got the engine out today and bike is now stripped of all old ICE parts and in the workshop ready for action!
http://www.youtube.com/watch?v=iGMotf9ozUo

Stripped and ready for action! First step is to order the magura twist grip throttle assembly.

Holy cow I've got to get one of those impact wrenches.

Good luck with the project !

BTW, going by the vids, the sprocket looks like it's a goner.
Chances are it - and the chain - has never been replaced if it's very slack.
If the rear wheel is near the aft end of its adjusting distance, the chain is gone - similar system to pushbikes, just sturdier.

Bike chains are pretty much standard - from what I can find, a CBR600 of that vintage uses a very common 530 chain.

can you describe the motors and batteries better in terms of size and weight? Are the motors going to be splined directly into eachother or what?

So far the only thing that concerns me about this is that you are a total newbie with bikes. Getting a few thousand miles under your belt with that thing could certainly influence your decisions when it comes to how to distribute that weight, placement of items, all those little component selections. Also, that low end torque that the DC motors can put out will be virtually the opposite torque curve of the motor you just pulled out. An entirely different animal. This isn't a bad thing but for bikes it's not ideal, will be harder to keep shiny side up. Not stopping ya, just a warning.. this obviously isn't a touring bike.

euromodder , thanks for the tip on the chain. I sorta figured it was shot but nice to know for sure. In any event it would be too short for the new drive setup.

Automcdonough , no need to worry i've about a half dozen experienced biker friends who are all volunteering to do the initial tests! I'll make sure i get correct training before hitting the roads..........oh that sounds sore:D Initial plan is to run the motors side my side and couple them with a short length of bike chain. I'll be keeping the weight as low as possible. The controller and charger etc will be up top. Original fuel tank will be going back on with its bottom cut out to house the new bits.

Just in after assembling the first motor. Of the two I got from the forklift place only one worked on test. I took the dead one apart and found all the brushes stuck and the com in bad shape. Took it to a local engineering works (guys that understand dc motors fortunatly) and they cleaned up the com and turned the shaft to 19mm. I spent a week of evenings cleaning out the com slots but obviously didnt do a good enough job. On first test the motor turned slowly and sucked amps. So i took it apart again and used a dremel with a .8mm milling cutter to get the slots perfect. Reassembled and hit the power. It nearly jumped off the bench with the torque and spun up to a nice steady whine:D

Motor number two will be getting the same treatment next week. I also machined off most of the center locating ring from the face plate leaving only 6mm. Cleaned up the faceplate as well. This means I can use almost all the shaft for sprockets.

I'd urge you to keep the same final drive setup - i.e. same position of the front sprocket as before.
It works well with the allowed movement of the swingarm in the Honda design - don't make it tougher on yourself than it need be.

An earlier EV m/c conversion that I've been reading about here on ecomodder, ran into a fair bit of trouble by completely changing the final drive lay-out (using rollers and pulleys etc.).

The load on those parts is very high, and with the high torque of an electric engine, it will possibly be even higher and also very instantaneous the moment you twist the throttle.

I don't want to (re)design your bike conversion, but make full use of the existing engine mounts to mount a very sturdy yet simple drivetrain.


The output shaft of the Honda gearbox (any bike gearbox) is very sturdy, and very much rock solid, ultimately being bolted to the engine bolts.
You want your design to be equally sturdy. ;)

Good advice. My only concern about the chain length would be if i have to increase driven sprocket size.

I was wondering what your solution will be to the frame. The engine acts as a stressed member in this frame if I'm not mistaken.

I agree that putting the bike up on the center stand should be easy. I have a Suzuki GS1150F that I can put up on the stand with modest effort. It's over 500 lbs and I'm 160. That said, I did need to learn proper technique. I did it wrong a few times and that made for a lot more effort. Your bike is much lighter.

I am thinking of converting an old Suzuki GS400E I have with a seized engine. Watching with interest.:thumbup:

honestly chains are a PITA. On my FZR it seemed like every 1k~3k miles I had to re-wax it and then adjust the rear wheel to keep the tension just right. I swapped it for a bike w/ a driveshaft and love it.

Since you aren't shying away from machine work, and the chain setup isn't even started yet, my vote is for driveshaft. There are plenty of touring bikes you could snag one from.
With any luck you could stack the motors directly on, or use a few gears w/ solid mounting plate.

Appreciate the vote of confidence but this is a budget conversion both in terms of money in time so i'll live with a chain. I do have an option on a bmw k75 for version 2 which is shaft drive:)

So I need a little advice on the sprockets. The bike's stock ratio is 2.87:1 with a 15 tooth on the engine and 43 tooth on the rear. So i've done some maths and came up with the following.
Wheel diameter : 600mm (approx)
so one turn = 1.885m
so for 1kph the wheel would turn at 8.83rpm

speed_________wheel rpm_______Motor rpm (2.87)_______Motor rpm (3.58)
50kph (30mph) = 441---------------1265-----------------------1578
100kph(60mph) = 883---------------2534-----------------------3161
145kph(90mph) = 1280--------------3673-----------------------4582

I can achieve a 3.58 ratio by keeping the stock rear sprocket and going to a 12 tooth on the motor. Bearing in mind its a twin motor setup I'm guessing i will have plenty of torque even with such a low ratio , still let the motor spin fast enough while holding them in the power band. Most bike conversion i've seen on the web have anything from 1:4 to 1:7 ratios but most are using agni or perm motors. Any advice much appreciated.

One thing that I never understood about electric bike conversions... Why do people keep using big motors (in this case dual motors) instead of a gearbox?

In the fifties all bikes had the engine and gearbox separate, with a short, heavyduty chain between... Get one of those, bolt it to the right place in the frame and use a single one of those motors... With three or four gears available that single motor should be enough for some serious speed and strong enough for burnouts in first gear if you like... And while a screaming 4 pot ICE from a newer bike would rip that gearbox apart, I'm fairly sure it will handle that power without flinching...

Well I happen to agree. Thing is that one of my aims for this project is to try out the dual motor system. If it works out great. If not i'll redesign. One option I am researching is a cvt from a snowmobile.

sportbike gearboxes are built into the bottom end of the engine, to use it will involve a bit of work. They also are built for an engine with considerably less low-end torque and a slipper clutch. It might separate ok and all you'd have to make are some covers to hold the oil in, but IMO dumping the gears is one of my favorite advantages of going electric.

As far as the ratio question, my vote is for the higher one (3.58).

What helped me make this decision for the E30 was looking up the transmission gear ratios. It turned out that 4th gear was 1:1, so that helped me get a feel for how much torque I was dealing with comparing stock motor torque to electric motor specs. You most likely don't have torque data on those suckers, maybe the best best is to set the max rpm at the highest speed you'd ever have the balls to go on that bike and pick the ratio from there. If you pick something reasonable like 100mph you could probly get away with something ~5:1. If it turns out to be fast enough at a drag strip then you could always swap the sprocket out, chains are an advantage with this.

Why make it complicated using a gearbox that needs to have a housing built? Like I said there are plenty of gearboxes with separate housings, and jackbauer obviously have found yet another option...

Dumping the gears have definete advantages, agreed... But given a choice of a large heavy motor on a bike, or a smaller, lighter engine with a gearbox (that's likely to be heavy, but decidely less heavy than the larger or second motor) my choice is simple... Gearbox it is... On a car it's an entirely different matter...

Yeh i'm gonna go for the 3.58. Firstly it sorta "feels" right to have the motors doing about 3krpm at 60mph and second it greatly simplifies (read cheap) sourcing sprockets and chain.

A smaller front sprocket will make the chain rub on the swingarm - some bikes will have a piece of rubber on the front end of the swingarm to keep this from happening as the suspension works.
12 is tiny.

I'd rather go up some teeth on the rear, than going down more than 1 on the front.


Don't run a new chain over worn sprockets for very long - it'll wear out the chain faster.

Torque maybe ?
Having a gearbox means having a clutch, so the clutch must be capable of handling the high torque of the electric motor(s).

Not sure i understand why a smaller drive sprocket would cause the chain to hit the arm. A larger one yes. Anyway I have an option on a 50t driven sprocket so i could use a 14t drive to get almost the same 3.58:1 ratio which is only one tooth less than stock:
Honda CBR600 FM-FT 1991-1996 50T Talon Rear Sprocket on eBay (end time 16-Aug-10 12:09:26 BST)

With less teeth the sprocket diameter gets smaller, so the chain tapers more toward the front, and the gap that the swingarm sits in gets narrower.

If that's the sort of ratio you want, I'd use the larger sprockets.

Well, yeah if you look at a modern 600 sportbike gearbox... But take a look at the gearboxes I mentioned from slightly older bikes, all with lower peakk hp and higher overall torque... And all of them designed by the same guy that designed the gearbox on the Queen Mary... The numbers say it would work...

Also, if you reduce the front sprocket, you increase wear on the chain...

Tighter bend, higher torque load on a smaller area/less links... And more overlap on the teeth count over the rotation... Go with the 14 front...

Ok need a little bit of advice regards chain joining. Seems they two ways are rivet and spring link. Looking on the web everyone seems to have a different opinion so my question would be is it ok to use a spring link in this application?

Jack,

You can get a master link for a 530 chain.

RK 530 X-RING Chain Master Link | Rocky Mountain ATV/MC

That way if you need to remove links, you just take a few off and rejoin the ends with the master link.

Cheep too!

-Adam

Well... There is a reason for that... They are both good, but for widely different purposes... Some overlap, some don't...

A clip link is good based on the fact that it's removable... On certain bikes you need to swap gearing a lot, ie trackbikes, or motorcross bikes and here that's large bonus... The downside is obvious, the spring locking the masterlink, can and do often fail and go missing... Not neccerarily because you are removing it very often, it can do so just because it feels like pissing you off... Check it regularily, and preferably use a safetywire to lock it...

On a roadbike, you will rarely swap the sprockets unless the chain and sprockets are worn out, so removal is a non-issue... A staked master link is stronger and completely maintainance free... It will last just as long as the rest of the chain, and doesn't need to be checked anymore than you check/clean/lube the chain... The downside? You need a chain tool to stake it... Can be done DIY style without one, but that takes some patience and knowledge... Best is to go down to the local bike shop, and they will usually stake the chain for you for free... Buying them a donut and coffee will usually get them to lend it too you for an hour or two...

Yes... You can use a clip-link... But I would recommend a staked link...

Thanks for that. I'll use the clip link for setup an initial testing with a cheap chain then switch to a quality chain and rivet.

Started to do some intital setup now that i have motor number one back together and taperlock sprockets fitted. Also got a 5 metre length of "10B" roller chain and 5 clip links from challenge power transmission for less than 40 euros. Turns out its the exact same fit as 530 motorcycle chain. Before everyone starts screaming that its not safe or not rated for a bike , relax. Its just for setup so i can determine the link count for the final chain and get everything lined up without worrying about screwing up.

I've ordered a 6mm endmill rated for hard steel so hopefully milling out the keyway on motor number 2 will be less a tour de force than last time .......

Motor Specs
 

Do you know the power output of the motors you are using, or their max rpm's. I apologize if I missed that part. Just wanted to make sure that you are not going to over rev them.

those pictures make me smile