BGF Hongdu/Solex
- Thread starter cannonball2
- Start date
I called Steve to check on my order.I ordered various parts, and some, he didn't have in stock. He was waiting for all parts to come in before he sent my order. He's sending rings now, stuff latr.
I asked him about which engine his rings fit. He sez both, the China and the Notchina engines.
I asked him about which engine his rings fit. He sez both, the China and the Notchina engines.
Just got my kit today. One question where do the wires connect to does any one have a wiring diagram? How do you wire the headlite?
Hey Monda, There is no diagrams or any other literature that comes with these.
most the wires under the headlight area are ground wires. One should be connected to a bolt on the fuel pump. One is for the connector tab at the back of the cover, for a taillight.
The cheezy lightswitch makes contact with the pointed brass pin that comes from behind the flywheel. If you don't see a pin there's prolly no light coil installed.
The switch and the bulb connector s are very crappy. Someone here soldered and wired theirs to run all the time.
You better pull off the front cover of the light and re-glue it with silicone.
On my 2 engine the covers fell off before I made 1 mile, crunching one.
most the wires under the headlight area are ground wires. One should be connected to a bolt on the fuel pump. One is for the connector tab at the back of the cover, for a taillight.
The cheezy lightswitch makes contact with the pointed brass pin that comes from behind the flywheel. If you don't see a pin there's prolly no light coil installed.
The switch and the bulb connector s are very crappy. Someone here soldered and wired theirs to run all the time.
You better pull off the front cover of the light and re-glue it with silicone.
On my 2 engine the covers fell off before I made 1 mile, crunching one.
The bulb in mine burned out pretty quickly. When I pulled it out it was mounted in a collar like a motorcycle bulb. Got to looking at it and they and ground the pins off a regular single filament bulb and pressed it into the collar. I did the same to replace it, dont thow the old bulb away you will need the collar. Best bet is to permanently wire the bulb from the insulated brass pin to run all the time, forget the switch, its erratic. If you want a taillite plug it into the brass tab sticking out of the back of the engine cover.
OK, I got #2 engine running pretty good. I noticed some gas dribble from the top of the carb.
It appeares that the fuel filter fits too loose to seat well at it's top flange, alowing sloshed out fuel to be sucked into the carb throat.
I put a ball point pen spring inside the fuel filter, to hold it firmly against it's seat at the top of thr carb.
I also added an o-ring around the air inlet flange of the carb /airbox junction. to replace the missing gasket that mine came without.
These two mods have caused the engine to run much better, way less 4-stroking.
My wife wants to try a MB, so i built this for her. Wanted it to resemble the old Solex bikes.
I installed a kickstand on the front axle. Works great to stabilize the front end when parked.
It appeares that the fuel filter fits too loose to seat well at it's top flange, alowing sloshed out fuel to be sucked into the carb throat.
I put a ball point pen spring inside the fuel filter, to hold it firmly against it's seat at the top of thr carb.
I also added an o-ring around the air inlet flange of the carb /airbox junction. to replace the missing gasket that mine came without.
These two mods have caused the engine to run much better, way less 4-stroking.
My wife wants to try a MB, so i built this for her. Wanted it to resemble the old Solex bikes.
I installed a kickstand on the front axle. Works great to stabilize the front end when parked.
Thanks, I cut and installed the fender today, then she took it for a ride with me following on my HS powered cruiser.
Gonna ditch the white saddle for a nice Bontrager. Prolly change to blackwalls too. They don't stay white long on MB's
The 2.25 tire clearance is just a little too close for safety . If the rim or tire wobbles more than 1/16" the tire is gonna show wear from rubbing on the sidewalls. Gonna look for some 1.195's
Good thing about the whitewalls I noticed is that they let you know they're rubbing early, by the white dust on everything.
Gonna ditch the white saddle for a nice Bontrager. Prolly change to blackwalls too. They don't stay white long on MB's
The 2.25 tire clearance is just a little too close for safety . If the rim or tire wobbles more than 1/16" the tire is gonna show wear from rubbing on the sidewalls. Gonna look for some 1.195's
Good thing about the whitewalls I noticed is that they let you know they're rubbing early, by the white dust on everything.
got my main jet fixed up. soldered it up and redrilled, stock size was .024 i ended up at .019 and it runs really good now. thats a #74 micro bit.
Well Engine #2 is running pretty good now, and seems to get a little stronger every hour of use.
Seems like the more power it makes, the better the rings start to seat.
It just takes patience to keep puttering along for a while until they gradually seat enough to make a little more power to load the rings enough to start doing some good.
It now climbs the long grade in front of my house and crests the hill at about 10 mph, whereas at first run, it would stop rolling if I didn't pedal.
Feels like about 18- 20 mph now.
It may have helped that I broke in this motor some on the front of my HS powered Sun cruiser. 2 engined bike was fun! I would use the HS to get it up to about 20-25 mph and hold it there a while at a time.
I had to use the enrichener lever at that high speed to make it run smooth. I figured all them revs for longish durations HAD to help wear the rings in.
I got my new rings and gaskets in for engine #1. Can't wait to see what difference a good ring fit does, without all the rounded ends, and a good roughish grit crosshatch hone to quickly seat 3 rings
Am I the only one that lost the dang headlight lens on the maiden voyage LOL
I love these lil engines. Thinkin about tryin a rear mounted one. Heard that's pretty common in Europe
Seems like the more power it makes, the better the rings start to seat.
It just takes patience to keep puttering along for a while until they gradually seat enough to make a little more power to load the rings enough to start doing some good.
It now climbs the long grade in front of my house and crests the hill at about 10 mph, whereas at first run, it would stop rolling if I didn't pedal.
Feels like about 18- 20 mph now.
It may have helped that I broke in this motor some on the front of my HS powered Sun cruiser. 2 engined bike was fun! I would use the HS to get it up to about 20-25 mph and hold it there a while at a time.
I had to use the enrichener lever at that high speed to make it run smooth. I figured all them revs for longish durations HAD to help wear the rings in.
I got my new rings and gaskets in for engine #1. Can't wait to see what difference a good ring fit does, without all the rounded ends, and a good roughish grit crosshatch hone to quickly seat 3 rings
Am I the only one that lost the dang headlight lens on the maiden voyage LOL
I love these lil engines. Thinkin about tryin a rear mounted one. Heard that's pretty common in Europe
Glad things are finally coming together for you. I think there is/was a light for sale on ebay. I am still running the ballon tires on my bike with no problems. The removal of one of the springs gives the necessary clearance and looses none of the tension necessary to drive the bike. I bought a set of brick tread tires off ebay for my Cranbrook build. They are a rounded profile, instead of the flat top that the bikes come with, should have plenty of clearance. The 1.95s are good to though.
nice bike wayne!
i've since ditched both hand levers on mine for a cleaner setup, i just didn't see a point to them. i can start the motor just fine under full compression, and although i used a rod that sticks up over the handlebars to open the compression valve to stop the engine, i really don't even need it because i can reach the lever itself with no trouble. i lost the clutch of course with no throttle, but that hasn't been an issue for me. my brakes will stop the bike but instead of killing the engine the roller will just skip over the tire. i think this has to do with my knobby tire, but also because i may not have the tension adjusted properly on the lowering bracket. it came out of the box full tightened and wouldn't budge until i loosened it. i may have it too loose. i've noticed i get better performance if i hold onto the lever knob and keep the roller just barely touching the tire. if i let it go, the roller has a tendency to dig into the tire and slows the bike down. i plan to rig up either a friction shifter or hand lever to raise and lower the engine, which a lot of friction drive bikes have. not only will it work as a clutch, but it will also let me fine tune the roller tension on the fly for optimal performance. seems more useful to me in this application than either a decompression lever or throttle.
i've since ditched both hand levers on mine for a cleaner setup, i just didn't see a point to them. i can start the motor just fine under full compression, and although i used a rod that sticks up over the handlebars to open the compression valve to stop the engine, i really don't even need it because i can reach the lever itself with no trouble. i lost the clutch of course with no throttle, but that hasn't been an issue for me. my brakes will stop the bike but instead of killing the engine the roller will just skip over the tire. i think this has to do with my knobby tire, but also because i may not have the tension adjusted properly on the lowering bracket. it came out of the box full tightened and wouldn't budge until i loosened it. i may have it too loose. i've noticed i get better performance if i hold onto the lever knob and keep the roller just barely touching the tire. if i let it go, the roller has a tendency to dig into the tire and slows the bike down. i plan to rig up either a friction shifter or hand lever to raise and lower the engine, which a lot of friction drive bikes have. not only will it work as a clutch, but it will also let me fine tune the roller tension on the fly for optimal performance. seems more useful to me in this application than either a decompression lever or throttle.
Im confused now camlifter on your redrilled jet. I ordered a micro set to redrill mine, and the chart listed the #74 as .0225. The closest to .019 is a # 76 @ .020 and the #77 is .018. It also shows a .5mm to be a .0197 which is in between #76 and 77. Which one is the one to use?
Thanks. I liked Cannonball's build, and decided to do a girls version for my wife. I peeled off all those busy, pink dolphin stickers, and that helped clean up the look a lot.
Now I want to do a men's model, rear mounted. Or, a ladies frame with red rims, to keep that Solex profile. Also, a big black seat with grabrail, on a layback seatpost. Now, dat be stylin' :~)
Maybe even put a motor on both wheels at some point LOL an go lookin for hills.
I think that your clutch may be stuck. I would investigate it farther.
On both my engines, at full throttle while stopping, the roller never skips, nor does the engines kill at full stop/full throttle. The clutches slip at this time.
If you experienced your clutch working right, you would never want to give up all the controls.
I can stop and idle easily now, after some practice.
Tip, when brakeing, adjust the throttle enough to stop the 4 stroking, and it helps you find the sweet spot for idle at a stop. It takes a lot of throttle to catch the sweet spot of the clutch for idle. Right before you are stopped advance the throttle for a split second
I like my throttle control cuz sometimes it wants to go faster than I do. Like when I'm looking for that headlight lens that fell off LOL.
With my compression release, I can push the bike about 3, quick steps, it starts, and I jump on, no pedaling off at all.
Alao on steep long hills, it helps with engine brakeing
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is it possible to remove the clutch components from the unit entirely and would there be any benefit from doing so?
my bits didn't come with a chart, i just micked them with my digital calipers. i used a #74 bit and it micked at .019, i had them calibrated about 6 months ago so i'm assuming there right. i soldered the jet and redrilled it one bit size smaller, tried it out, then resoldered it again and tried it out, ect.ect. untill it ran good, ended up at the #74.
as for the clutch mine was not working untill after about 20 miles it freed up and now works good, give it some time.