what did you do to your motorized bicycle today?

GoldenMotor.com

curtisfox

Well-Known Member
Dec 29, 2008
6,041
3,935
113
minesota
You mentioned you had nobbies,most of the is the tread,nobbies have a lot of drag,and are really not good for road. Even the cruiser with nobs,have drag I have a Cannondale that come with nobbie change them to a Kenda with smooth centers and slight nob on the outside, like having a hole new bike,just my experiance ...............Curt
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
last eve, I ran a heavy chain thru my bike & two I have for sale - a customer called that afternoon to say his was stolen from his yard a couple blocks from me : (
 

tgaydos

New Member
Jul 16, 2015
108
1
0
astoria oregon
it felt like it ran better with the road tires but now it won't start, i rode it 16 miles today and now it won't start, it ran out to the place just fine but went to start it up to show a coworker and nothing. it's showing similar signs to when i first tried starting it.
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
most likely thing is petcock left on & motor full of fuel, next thing is wire came loose, also could be one of the CDI units we all had trouble with a few months ago that has gone weak
 

tgaydos

New Member
Jul 16, 2015
108
1
0
astoria oregon
i checked all of this last night but will check it again today, now that i'm not pissed and beat to ****, it's a bit of a beast to peddle that thing 16 miles over two bridges home. i made sure to shut off the petcock and the carb valve when i stopped but it is possible. i think i rode the whole way home with it on because i'd try and fire it every so often to see if it'd go but no dice. i'll pull it all apart today and see, possible rings? i ramped and notched my piston a while back. also may be the base gasket even though i just replaced it? i'm not ruling out anything until i pull it tonight though.
 

tgaydos

New Member
Jul 16, 2015
108
1
0
astoria oregon
i've got a new magneto coming as that's the only thing i can think it is after having tested all the other things. mechanically it's fine and it's getting fuel, there's no way i burned up two plugs and two cdi's in the short time i've had the bike.

I got new hardware yesterday for the motor and i had a pain in the ass time trying to find the sizes, i ended up taking one of each bolt in to fastenal and get it matched up that way. Here's what i came up with for sizes and part numbers from fastenal. They're all hex cap screws.

Sprocket cover: m6-1.0 x25mm; pn 1139568
Clutch cover: m6-1.0 x20mm; pn 1139567
Case mount: m6-1.0 x35mm; pn 1139570
Magneto cover: m4-.70 x16mm; pn 2139526
Case bolt below the jug: m6-1.0 x40; pn 1139571
Head studs: m8-1.25 x90mm; pn 1139599

This is for my flying horse angle fire from bike berry.
 

Tony01

Well-Known Member
Nov 28, 2012
1,730
1,722
113
sf bay area
Finished cutting and grinding/shaping my 2-speed jackshaft plates. I was cutting and grinding these for about four days. Each plate is 3/16" iron and weighs a bit over a pound. Once I get the setup solid and it comes time to paint, I will remove the plates and drill around 40 holes to remove a pound!!

The big issue right now is chainline and deciding if the final drive sprocket will be between bearings or not. I drew the assembly in solidworks before starting and planned on not between, but now in putting it together I can see there is more space than anticipated.
 

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Tony01

Well-Known Member
Nov 28, 2012
1,730
1,722
113
sf bay area
Yea I would like to put a rear suspension pivot right on the rear jackshaft but there isn't enough room on the shaft anyway. I could put it just behind the JS and the chain slack due to misalignment would be minimal... But man it's a project for another bike I think. The engine is a briggs & stratton 3.5hp- 148cc and the block you see is a worn out aluminum bore block. Have a thread in hubs/gearboxes on this transmission. Here is my first solid mockup with JS solid. The slack between shafts will be adjusted by moving bearings, the overall slack bias can be moved forward or back to tension or loosen the engine chain while doing the opposite to the final chain, and the entire assembly can be moved up and down the seat tube which will adjust slack for my pedal chain which connects to the rear jackshaft.

Is it normal to be working on your bike till 3am?
 

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Davezilla

New Member
Mar 15, 2014
2,705
10
0
San Antonio Texas
Still making slow progress because it's been crazy busy at the shop this summer but I assembled a Super Rat engine for the mountain bike installed a crank set off an older schwinn mtb but the small chain ring was hitting the swing arm so I took it off and tried a few other crank sets I got sitting around, they all hit so I went ahead and ordered a Specialized jis crank set since it had the right offset and will clear the swing arm. The frame tubing on this bike is also wider than the engine mount's stud spacing so I ordered a piece of 1 inch thick 6061 aluminum bar stock so I can make the custom mounts on my cnc. My plan is to join 2 pieces then rout out the hole for the frame tubing for both the front and rear mounts since the seat post tube is also quite a bit bigger than most bikes and wider than the stud spacing on the rear mount as well.
This will make for a nice solid mounting setup that won't harm the aluminum frame tubing.
I also zip tie mounted the engine to the frame as a mock up to see how the CR 80 pipe will fit and what bends will need to be re clocked. I like the CR 80 pipe's shape since it also looks like only one bend will need re clocking for it to fit perfectly, and the stinger points to the back of the bike perfectly so a lot less modifying will be needed there. I got a set of wheels on the bike now so I can roll it around to and from where I'm working on it but I'm also thinking about making up a set of wide 24" rims or lacing some 50mm wide rims to my hubs, unless I can find a 24" rear well with a disc brake hub and a really wide rim pre made.

I didn't have enough time to mess with the road bike but I'm going to take some measurements so I can make some billet brackets to secure the pipe to the frame , I just need to weld a few spring mounts to the pipe and find a way to secure the back of the pipe then it'll be ready to start the engine and start breaking it in.
 

tgaydos

New Member
Jul 16, 2015
108
1
0
astoria oregon
i didn't do anything, i'm waiting on payday so i can get a new rim since i hit a pothole and put a nice flatspot in the rim, and the other donor rim i had doesn't fit the spokes as it's a mtb rim instead of a cruiser rim, different shapes where the spoke sticks through. and i'm still in need of a sprocket for my peddle side.
 

DaveC

Member
Jul 14, 2010
969
1
18
Boise, ID
Still plotting and planning the electric rear hubdrive on my West Coast Special. Going with a 24 volt 500 watt motor and 2 tractor starter batteries. Going for mileage not speed ;)
 

Uncle Bob

New Member
Sep 1, 2015
29
0
0
68
Walla Walla. WA
I rode mine to work and back home again, as I do everyday. Now I'm planning my next build, a Lifan 98cc ohv with a moped rear hub, drum brake, right side freewheel peddle sprocket and left side variator pulley with built in 12.5-1 reduction laced to a 26 inch bicycle rim. and the planning continues.
 

Davezilla

New Member
Mar 15, 2014
2,705
10
0
San Antonio Texas
Finally finished welding up the KX65 pipe so it fits my road bike... I got it fitting really nice but had to re aim the stinger so it wasn't blowing right at my crotch, then I added about a foot of tail pipe to the whole thing so now it runs about 6" behind the seat post and points straight back. I'm going to run it like this and see if it's going to be too loud. I got a Pro Circuit muffler I can fit onto the pipe if it's louder than I'm expecting...

For the Mountain bike, I'm waiting on some aluminum bar stock and the new crank set to come in, then it's off to CNC land to carve out some custom mounts. I got a Pro Circuit pipe off a CR80 for this one but I need to get the engine mounted before I can even think about cutting and re clocking the pipe to make it fit...
 

Davezilla

New Member
Mar 15, 2014
2,705
10
0
San Antonio Texas
Got the new crank set for the mountain bike and no more interference problem with the sprockets hitting the frame... This set also has interchangeable sprockets so I'll be able to remove the ones I'm not going to be using since I'm setting this one up as single speed and will only be using the small sprocket so I'm going to remove the other 2 sprockets before locking this one down.
 

tgaydos

New Member
Jul 16, 2015
108
1
0
astoria oregon
i took it for a ride today and popped one of my new head bolts, it pulled out from the case luckily i still have the studs to put back in and they'll thread all the way in.