Cannonballs Back Into It With A BT 80

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cannonball2

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Oct 28, 2010
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Colonial Coast USA.
Thanks Curt!

Wanted something with an integrated spring instead of having the usual stretched spring having to be anchored somewhere. Its easily adjustable for tension just by loosening the center bolt and rotating the caliper to add/subtract tension. Also didn't want to mount the idler to the lower chain stay/frame. Just don't like em there.

Working great so far.
 

curtisfox

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Dec 29, 2008
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Have to remember that if i ever do a chain drive( belt man here ). I can see were it would be so much better than a pull spring, i like it ............Curt
 
Jan 17, 2015
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Push button start...love it!! Dang I never thought of the caliber tenstioner..already spring loaded..what an no fiddl'in with adjustment..I discovered how important proper chain adj is. I tightened mine up and smooth take offs now...imagine that...duh
 

cannonball2

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Oct 28, 2010
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Colonial Coast USA.
Yeah chain adjustment is important. I often overlook it. That's why I favor a spring loaded idler. For the most part it handles the adjustment automatically assuming the chain is properly set up in the first place. I would have run a skate board wheel but clearance was critical and the stock idler worked perfectly.
 

cannonball2

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Oct 28, 2010
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Have been riding a few miles almost everyday. The weather had been pretty nice with highs in the 70s. Perfect!

Replaced the original motor oil in the gear case/clutch with 80/90wt. The gears are much quieter. Was wondering how the clutch would handle it. Works as it always has. Might be different if I lived where it gets really cold. Not an issue here.

I am coming to believe this engine is in a class by itself. About all it has in common with a CG is the mounting and carb. Runs very well, and is super smooth. In stock form its a very hard puller with plenty of low end and a willing revver. With the exception of the recoil has had zero issues. I'm liking it a lot!

Bought a Batavus moped front end to replace the springer. Was cheap enough. and should look and work pretty decent.

Seems Bikeberry has concluded I'm not due a recoil as I have not heard back from them. Contacted them twice and included pics. Probably aren't any any way. Doesn't matter really the electric start is way over built for this engine.Should last a long time. Doesn't even phase the Lipo. The included kit battery fit my Vespa perfectly.

Just expected better from Bikeberry. I have always had good service from them.
 

cannonball2

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Oct 28, 2010
3,682
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Colonial Coast USA.
So how do you turn a rather homely little engine with and industrial cylinder into a motorcycle engine wannabe?

Like this. Too funny. Its all faux. CG head will just screw down on top of the cylinder. I imagine it will add some cooling and will nicely carry an extra plug.

My 1969 Yamaha DT1 actually had a head that carried an extra plug. If one plug fouled just swap the plug wire and go on.
 

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cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
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Colonial Coast USA.
My first "motorcycle" was a 46 Cushman, followed my a 57 Triumph Tiger and on and on. Rode just about any thing and everything over the years. Down to what may be my last, a slightly warmed up 06 KLX250. Sorta full circle to where I started.

Getting ready to add lights and was searching wiring diagrams. Since the electrics are borrowed from basically a pit bike it follows that pit bike electrics fit and work.
Advantage here is the ignition. With little fuss this engine will run the pit bikes CDI. It consists of a CDI box and separate coil. Its the same coil used by the aftermarket CG performance CDIs out there.

For anybody tuning one of these engines there are numerous CDIs with different features like different timing curves and no rev limiters. Cheap too like $10. Wow two for $10+

http://www.ebay.com/itm/2pcs-90CC-1...ash=item2374ea1bce:g:kB0AAOSwxKtYBdul&vxp=mtr

Thought Id through this in. Seems little is being discussed/known about this engine. Nice to know some details.

I will add that these units are for 4strokes however as cheap as they are would be fun to experiment with.
 
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cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
63
Colonial Coast USA.
Here a quick lesson on lighting and voltage regulators.

I want to run lights with no battery. There are lighting coils to run both lights and to charge with. Since I am running filament bulbs(this wont work with leds) I don't need DC voltage AC is fine for bulbs. I could hook up directly(no regulator) to the coils but at high rpms the bulbs will terminate due to excessive voltage.

So you run an AC regulator. These are a bit hard to find, but cheap. I found this one for $10 on ebay. Simple to wire, the black grounds and the yellow hooks in parallel to the lighting circuit. That's it. It shunts excessive voltage to ground.

The regulator on the left came with the kit it is a regulator/rectifier. Converts the AC to DC for charging a battery. Will also run only lights, but will blow bulbs with out the little AC regulator. Ask me how I know. It wires with the lighting coils going to the yellow wires the green to ground and the red is voltage to load. Also very easy.

So now you know about simple V regs.
 

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cannonball2

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Oct 28, 2010
3,682
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Colonial Coast USA.
So here the finished faux head.

I ordered a new head as the first one got cut both front and back to see which way
worked the best. A whopping $9.99 shipped.
Notched the front to allow the plug clearance and trimmed the edges a bit.
Its screwed to the existing head with specially ground(head)#10 screws to fit between the fins. Nuts are slipped between the top and second fin for the screws.
It actually gets hot and dissipates heat like a head should.
Thought about adding a second faux plug wire for the twin plug look, but will for now leave it as a head with a secondary back up plug like the old dirt bikes used. Looks a bit more motorcycle than backpack blower. This in not the first engine to sport a fake head.

This has nothing to do with anything, just something I wanted to do.
 

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MEASURE TWICE

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Jul 13, 2010
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That interesting! No so much for esthetic looks on my bike, I was thinking of adding some kind of cooling fins. I want them attached to the cover plate on the cylinder toward the front. The cover is for the fan blade on the flywheel to route air around the cylinder. A little more cooling while moving with added fins may help some.
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
63
Colonial Coast USA.
That interesting! No so much for esthetic looks on my bike, I was thinking of adding some kind of cooling fins. I want them attached to the cover plate on the cylinder toward the front. The cover is for the fan blade on the flywheel to route air around the cylinder. A little more cooling while moving with added fins may help some.
Maybe you could bolt on a second stock head using longer head bolts. Might fit right over the cooling shroud with no problem.

Thanks for the comments Scratch and Dogcatcher(really?)

Should have the moped front end tomorrow and will begin the change over. Hope its a bolt on or close. For got I have a NOS 1965 Suzuki 100 front end in the attic. Oh well use it on something else.
 

s1rvr15

Member
Jan 16, 2016
65
3
8
Hales Corners, WI, USA
Nice build! Couple of questions for you (which I hope are in your wheelhouse):

How did you rig up that fake head? Are the holes in the jug just threaded, or did you have to do something else?

I ordered one last week (expected to come in on Thursday, I get to build on a day with a high of a whopping 8 whole degrees), and I was also wondering how difficult it would be to rig up a switch, relay/flasher, and some 12v motorcycle turn signals (I plan to weld some coupling nuts onto the stem and my rear rack to hold them)?

Also, how did you drain out the clutch oil? Is there a drain screw, or was it a case of tipping it on its side and letting it out after warming it up?

Do you think it has the grunt, bone stock, to pull a 115lb rider on a 25lb road bike with a 36T sprocket and 27" wheels without pedaling?

Finally, no shock with the reception you're getting from Bikeberry. They're one step above Kings/Gasbike in the sense they actually ship your stuff, but leave you completely out to dry if it is defective or damaged. ****, I had to complain through the BBB in order to get them to reply to my emails. Not sure why I always get such bad service with them, because everybody I spoke to on my many phone calls to them (including Jack, the owner of the company) is incredibly nice.
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
63
Colonial Coast USA.
The head is just attached with a couple of screws and nuts to the top fins on the cylinder. The head nuts are fake/non functional.

If you are going to build the complete kit with the battery, turn signals would be no problem. The clutch side has a drain, but at least the way my bike sits it drained faster by removing the clutch cover.

Its a very torquey engine. It pulls my 175 lbs with a 41t with 25.5" overall tires very easily from stand still. Climbs the few hills(bridges) we have here in the flats with no problems. and rides trails quite easily. I would compute the ratios for your bike, 27" wheels are pretty tall. I would think something in the low 40s would be better. It was designed for a 26" with a 44t. Mine came with a 48 which I never used.

You will find this to be a well designed, complete quality kit. The biggest issue is getting all the stuff(with the full kit) situated on the bike. I actually used very little if the kit.
 

s1rvr15

Member
Jan 16, 2016
65
3
8
Hales Corners, WI, USA
That makes sense.

Good to know, thank you.

I guess I'll try it with the stock 44 before I try the 36 off my MTB and see how it goes, the 44 with 26" wheels vibrated way too much at any usable speed for road travel (pretty much 25 in my area).

And yeah, things like putting the battery under the BB are really dumb, I plan to put it on a rack. And from what I see, the stock box for all the electronics seems kinda badly designed, no watertight seal, and it could've been shaped differently to follow a top tube better and thus look nicer.
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
63
Colonial Coast USA.
This engine is so much smoother higher revs aren't the issue they are with a CG.
You may also get a 48t in the kit. Manual lists a 44. Hope you get one. With out running ratio calcs 44 would sound about right for a 27 high gear.

Wiring is laid out for mounting pretty much as the instructions indicate. You will have to extend it for rear rack mounting. The battery is an agm so can be mounted laying down. The kit is a bit awkward esthetically but is well thought out fuctionally.

The engine starts so well on the small lipo that a smaller SLA battery probably could be used.
 

curtisfox

Well-Known Member
Dec 29, 2008
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minesota
WOW! Sure glad someone come out with a better motor, or at least one you don't have to fix out of the box. And more trouble free, be a lot less tassel for some of the new comers. To bad they can't do a good recoil start, maybe make a cone like the old Briggs had, they never failed LOL. Glad to here a lot of + on these, and thank you for going through all this and letting us know. ...............Curt