bighead
New member
looks great friend. Better than I thought it was going to. Nice work.
Motorbike forks for a minibike
- Thread starter landuse
- Start date
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I am going to use a jackshaft and my little 3HP Briggs. I have a 16T clutch, 14T in, 38T out the jackshaft, and a 48T sprocket on the rear wheel. I just have to get the 48T machined to get the boss off it, and drill some more holes in it.
The brakes I will try and sort out this weekend. They are coming off a pit bike I bought.
Tomorrow is a public holiday for us, so I will get some more work done. Updates coming soon
bighead
New member
What holiday would that be? Just wondering.
It is called Youth Day. This is from the Wikipedia document relating to it.
"The Soweto Uprising, also known as "June 16", was a series of student-led protests in South Africa that began on the morning of June 16, 1976. Students from numerous Sowetan schools began to protest in the streets of Soweto, in response to the introduction of Afrikaans as the medium of instruction in local schools [1]. An estimated 20 000 students took part in the protests, and roughly 176 people were killed.[2] The 16th of June is now a public holiday, Youth Day, in South Africa, in remembrance of the events in 1976."
Funnily enough, for the last 20 years or so, the Comrades Marathon has been run on this day. It is about 90KM (56 miles) marathon between Pietermaritzburg and Durban. They give you 11 hours to run it. I ran it once in 2003. They have now moved the race to another day, cos the government says that the day is now known for Comrades, and the real meaning of the day was being lost. Comrades is a big thing here. The race is broadcast on TV the whole day from start to finish.
Youth Day
Comrades Marathon
"The Soweto Uprising, also known as "June 16", was a series of student-led protests in South Africa that began on the morning of June 16, 1976. Students from numerous Sowetan schools began to protest in the streets of Soweto, in response to the introduction of Afrikaans as the medium of instruction in local schools [1]. An estimated 20 000 students took part in the protests, and roughly 176 people were killed.[2] The 16th of June is now a public holiday, Youth Day, in South Africa, in remembrance of the events in 1976."
Funnily enough, for the last 20 years or so, the Comrades Marathon has been run on this day. It is about 90KM (56 miles) marathon between Pietermaritzburg and Durban. They give you 11 hours to run it. I ran it once in 2003. They have now moved the race to another day, cos the government says that the day is now known for Comrades, and the real meaning of the day was being lost. Comrades is a big thing here. The race is broadcast on TV the whole day from start to finish.
Youth Day
Comrades Marathon
bighead
New member
Thanks for the info. I knew I would learn somthing.
Well, even though it was a holiday, I didn't get too much done. I did figure out that in my haste to build the rear end of the bike, I didn't fully plan for where the back brake is going to go. 
I am therefor going to have to scrap the hydraulic brake, and go with a mechanical one. I will have to weld a bracket to the frame to mount it. Maybe I will be able to get the steel and do it this weekend. Pic 1 sort of gives you an idea where it is going to go. I was also going to use a foot brake for it, but i think I am going to go with a brake lever (where the clutch lever would go).
I also got the foot pedals ready for welding. They came off the original frame that I bought. I will do that this weekend as well. I also swapped the handlebars out with my pitbike frame, so I have all the levers etc on now.
I now need a bit of advice/help on what everyone thinks I should do for a seat. I have take 2 pics. The seats are not what I will use, but you can get the idea of the style I am looking at. Should I go for the flat seat look, or the pitbike seat look. Whay do you think.
I also scored a new engine yesterday. It even has a reduction box with clutch. I got it for about $30. I haven't been able to get it going yet, but I haven't had much time. It has spark and compression, so I think I will just need to clean the carb out. I thought it would be a good project for me to learn how to repair small engines. I might take it apart and reassemble it.
I am therefor going to have to scrap the hydraulic brake, and go with a mechanical one. I will have to weld a bracket to the frame to mount it. Maybe I will be able to get the steel and do it this weekend. Pic 1 sort of gives you an idea where it is going to go. I was also going to use a foot brake for it, but i think I am going to go with a brake lever (where the clutch lever would go).I also got the foot pedals ready for welding. They came off the original frame that I bought. I will do that this weekend as well. I also swapped the handlebars out with my pitbike frame, so I have all the levers etc on now.
I now need a bit of advice/help on what everyone thinks I should do for a seat. I have take 2 pics. The seats are not what I will use, but you can get the idea of the style I am looking at. Should I go for the flat seat look, or the pitbike seat look. Whay do you think.
I also scored a new engine yesterday. It even has a reduction box with clutch. I got it for about $30. I haven't been able to get it going yet, but I haven't had much time. It has spark and compression, so I think I will just need to clean the carb out. I thought it would be a good project for me to learn how to repair small engines. I might take it apart and reassemble it.
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bighead
New member
How is the reduction unit change your gearing? or does it?
Nice score. I would see if it runs before you tear it apart. Have you tried dumping about a 1/2 teaspoon of gas down the plug hole?
Nice score. I would see if it runs before you tear it apart. Have you tried dumping about a 1/2 teaspoon of gas down the plug hole?
The reduction box has a 2:1 reduction. Your gearing would be divided by 2 if I understand it correctly. (Eg. from 3:1 it will go to 6:1). I have another one on my Honda GX140. They go for big money here, so I could probably sell it and make some money.
I only got it late in the afternoon yesterday, so I haven't really tried much yet. I pulled the starter till my arm was sore (it still is). I see there was some gas dripping out the bottom of the carb bowl, so I think the carb might not be on properly.
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bighead
New member
Is the plug wet after all that pulling or dry? I would dump a small amount of gas down the plug hole.
I will try it when i get home today and let you know. I have a problem trying to get the plug out, cos the muffler is in the way of the tool I use. I am going to have to figure something out.
fowler
New member
unless i am mistaken and this is nothing like our gx140 then u can take the air filter off and it makes removing the spark plug alot easier
id assume u have a spark plug socket?
id assume u have a spark plug socket?
Yup, I have a plug socket. It is a bit too long to get it in the tight space though. I am going to take the muffler off this weekend and see what I can do. The air filter will not cause too much hasstle. Its the muffler thats the problem
fowler
New member
well bugger ay
A small update. On saterday I decided to work on the engine that I am going to be using for this bike. It hasn't ben running well, and all I thought it really needed was a carb clean. So I got the engine out, bolted it to the workbench and got going. I used THIS link to give me a hand in the dissasembling and cleaning. THIS link is also helpfull with identifying Briggs carb problems.
The first couple of pics are of the carb before I removed the thing. I took Bigheads advice and boiled the carb in lemon juice, cos I didn't have any carb cleaner handy. After that I cleaned out all the jets and holes with a copper thread from a wire brush. Some of the holes were quite dirty. After putting it all back together, filling the tank etc, I had to put some fuel down the plug hole to get it going.
I still had a problem in that i could get it running, but not idle properly. It would keep on dying. If I incresed the idle, it would then idle high, but at least I could rev the engine. SO AT VERY HIGH IDLE I COULD REV (SORT OF), WHILE AT IDLE IT JUST BOGGS DOWN. I decided to clean it again yesterday with some carb cleaner I bought, and it is still pretty much the same.
I have a vid of the engine running and bogging down that I will upload for you soon.
I also finished the seat for the bike yesterday. I welded the old pit bike seat bracket onto my frame, and then cut out a piece of board the size I wanted it to be. I then cut 2 pieces of foam the same size as the board, and covered it with some yellow couch material we had lying around. My wife helped me with the covering. As you can see, it looks like crap on the bottom. I used both nails and glue gun glue. I think it turned out pretty nice. It gives the bike a really unique look.
The first couple of pics are of the carb before I removed the thing. I took Bigheads advice and boiled the carb in lemon juice, cos I didn't have any carb cleaner handy. After that I cleaned out all the jets and holes with a copper thread from a wire brush. Some of the holes were quite dirty. After putting it all back together, filling the tank etc, I had to put some fuel down the plug hole to get it going.
I still had a problem in that i could get it running, but not idle properly. It would keep on dying. If I incresed the idle, it would then idle high, but at least I could rev the engine. SO AT VERY HIGH IDLE I COULD REV (SORT OF), WHILE AT IDLE IT JUST BOGGS DOWN. I decided to clean it again yesterday with some carb cleaner I bought, and it is still pretty much the same.
I have a vid of the engine running and bogging down that I will upload for you soon.
I also finished the seat for the bike yesterday. I welded the old pit bike seat bracket onto my frame, and then cut out a piece of board the size I wanted it to be. I then cut 2 pieces of foam the same size as the board, and covered it with some yellow couch material we had lying around. My wife helped me with the covering. As you can see, it looks like crap on the bottom. I used both nails and glue gun glue. I think it turned out pretty nice. It gives the bike a really unique look.
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Here is the vid I spoke of
http://s1103.photobucket.com/albums/g477/landuse01/?action=view¤t=briggs.mp4
http://s1103.photobucket.com/albums/g477/landuse01/?action=view¤t=briggs.mp4
So what do you think the problem with my engine is? I am at a loss.
bighead
New member
Not an engine guy so wish I could help more. It sounds like air problem if I was to guess. Governer hooked up right? Does a briggs carb have a main jet and iddle jet? Does it have an air screw?
This carb is pretty simple. All it has is a fuel mixture needle. It controlls the idle. There is no air screw at all. It has high and low discharge ports under the needle seat that I cleaned out well. Otherwise, this thing is pretty simple.
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I was able to get some plate steel for my motor mount yesterday. I cut it to size and have nearly finished welding it to the frame.
I also had to buy a new master cylinder for my front brakes, because I figured out that my existing one is scored and scratched in the barrel part, and the bike place near me said it wouldn't work anymore. I was able to get a really cheap secondhand one though.
I also dropped off all my sprockets and jackshaft axle to get keyways cut in them. The one sprocket also had to get the boss machined off.
Everything is coming along nicely. Hopefully in the next couple of weeks I will be able to take this baby for a test drive!!!
The first pic is of the engine and jackshaft mount. I went with 4mm plate steel. I will add a brace or two. The second one shows some of my welds. I am definately getting better. I am still using a 120A stick welder with 2.5mm 6013 electrodes.
I also had to buy a new master cylinder for my front brakes, because I figured out that my existing one is scored and scratched in the barrel part, and the bike place near me said it wouldn't work anymore. I was able to get a really cheap secondhand one though.
I also dropped off all my sprockets and jackshaft axle to get keyways cut in them. The one sprocket also had to get the boss machined off.
Everything is coming along nicely. Hopefully in the next couple of weeks I will be able to take this baby for a test drive!!!
The first pic is of the engine and jackshaft mount. I went with 4mm plate steel. I will add a brace or two. The second one shows some of my welds. I am definately getting better. I am still using a 120A stick welder with 2.5mm 6013 electrodes.
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