Pappy, Welcome. Your Posting Now. Post All The Pics You Wish. Bears Love Honey! We Prefer Pics. Ron
Very satisfied with my first build!
- Thread starter a_dam
- Start date
Thanks Neat Times,
I see your from Pensacola, FL. Im a P'cola native,
This is my first project in progress.
crap....it won't let me post pic's....
I see your from Pensacola, FL. Im a P'cola native,
This is my first project in progress.
crap....it won't let me post pic's....
ok, I think I got it now.
This is my first project
This is all bolted together, waiting on parts for my weilder.
As you can tell, Im no pro like you guys
It took 3 bikes and a mini pocketbike to make this 7ft 4in monster.
This is my first project
This is all bolted together, waiting on parts for my weilder.
As you can tell, Im no pro like you guys
It took 3 bikes and a mini pocketbike to make this 7ft 4in monster.
Last edited:
Hi Pappy, And Welcome, Thanks For Sharing. I`m A West Centrall Wisconsin Native, Been Here 18 Yrs. Your Build Looks Good, Lots Of Thought Went Into It. Congratulations. Ron
First Test Run:
There seems to ba a problem, it has no pull. I think it's in the drive/chain transfer, as it is now, the sprocket order is small to big to big to small if I go from small to big to small to big as if it were a single chain drive, do you think it will pull?
There seems to ba a problem, it has no pull. I think it's in the drive/chain transfer, as it is now, the sprocket order is small to big to big to small if I go from small to big to small to big as if it were a single chain drive, do you think it will pull?
Attachments
Pappy, Yes - I Think Your Correct In What You Need To Do. If You Give Us The Engine Size And The Number Of Teeth On Your Diagram Spockets, We Can Figure Your Ratio. You Can Do This Before You Do The Changes. Also Make A Diagram OF With Tooth Count And We Can Give You A Current Final Ratio. When You Switch The Secondary Sprockets It Will Make A Large Difference. Ron
Pappy, Your Original Setup Would Give You A Final Ratio Of 2.13 : 1= No Good!! You Did Not Give Engine Cc. Is There Any Gearing In The Motor? Or Is The Sprocket Rite On The Crankshaft? Is There A Clutch. If There Is Some Gearing In The Engine That Changes Everything. When You Change The 2 Secondary Sprockets Your Ratio Goes To 9.5 : 1. Much Better. Your Final Ratio Should Be Approx 15 To 18 To One. You Are Halfway There. I Think Your Engine Must Have Some Gearing.
Pappy, I See You Have 8 Tooth Sprocket On Motor. That Means That You Have A Centrifical Clutch With 1/4" Pitch Chain. You Will Have To Change To Your Second Diagram. That Will Give You A Final Ratio Of 9.5:1. You Will Need About A 54 Or 63 Tooth On The Rear Wheel. Depends On Your Wheel Diamiter. Ron
Your Engine Could Be 33 To 49 Cc. You Will Just Burn Your Clutch Up If You Do Not Have About 63 Tooth On Rear Wheel. If You Get The Clutch To Hot And It Sticks, It Will Not Come Off. I See Your Secondary Chain Is Larger, Is It 8mm?? ARE YOU GOING TO BE ABLE TO PUT THE 17 TOOTH ON THE JACKSHAFT. YOU WILL THEN NEED THE 63 TOOTH ON THE REAR WHEEL. THAT WILL GIVE YOU A FINAL RATIO OF 16.7 : 1. THAT SHOULD WORK OK. Ron
Last edited:
The engine is a 49cc, so the second diagram will work if I use a much bigger sprocket on the rear? ho, the rear wheel is a 20 inch.
I got up in the middle of the night thinking about your problem. I thought I had the AH-HA moment but you already inverted the sprockets in Diagram B. Neat is correct in that you need more reduction. But where are you goin to find a 63T? I bet you have better luck with two 50T's. Neat Times could you please run the numbers with two 50T's instead of 36T's in Diagram B? It's 4am and I'm no good at it even at noon. Not even trying now. LOL
Good luck!
Good luck!
Hi Ozzy, Welcome To The Forum. You Can Find The Sprockets On The internet. 54, 63, 72 And I Think 80 Tooth. They Are For Pocket Rockets. They Have Them for 1/4" or 8mm Pitch Chain., And Some #35 Chain. I Do Not Know What He Is Using. It Looks Like He Has 1/4" On Frt And Larger On Rear. If He Will Post What He Has We May Be Able To Get Him Close. In Diy Cvt Belt Drive My Build Has 8mm Chain. I Have A Freewheel Hub With Sprocket Bolted To It, On The Rear Axle, It Is A Big Plus. Ron
Attachments
Last edited:
I will post some close up pic's of what i have to deal with, bear in mind that I have no flipp'n idea as to what I am doing, I only started this thing because I lost my DL and have been walking for the past 6yrs and Im running out of shoes. I'll take all the help I can get. I don't work, my helth won't let me, so I have very little income, I need to be moble again, even if it's the last thing I ever do.
Scott
Scott
hey scott, lots of people in the same boat. have you been able to switch the sprockets? it will still be way off from the needed ratio. is your rear chain different from the front chain?? get us as good of closeup of the secondary sprockets. a good pic of the large frt sprocket also. do not run the front chain to tight. the frt bearing and sprocket could fail. they have a new style clutch cover housing now, it has a 3rd bearing on the outside of the sprocket. that little sprocket is about the size of a dime. you did a great build. i would say you are very good bolting things together.
How can this pocket bike motor have such a small rear sprocket? And Pap needs big one the rims are that big a difference?
http://motorbicycling.com/attachments/f3/7703d1240412198-new-build-pocket-bike-motor-dsc06371.jpg
http://motorbicycling.com/attachments/f3/7703d1240412198-new-build-pocket-bike-motor-dsc06371.jpg
Hi Ozzy, I Think He Is Geared High Also. I Think He Said He Pedals A Lot And Just Wants Assist. If I Remember Rite, He Gets Over 200 Mpg. He Did A Great Build. I Was Going To Try Calculate His Gear Ratio. The Chain Trans Is 3.25:1. I Thought He Mite Have A 10 Tooth Sprocket On The Trans But The Chain Looks Like It Is Going Around A 19 Tooth Or Larger. I Looked At His Posts The Other Day, Can`t Remember The Thread. Ron
Hi Pappy.
On your jackshaft diagram you are going from motor to jackshaft, jackshaft to wheel. You have 8 to 36, 17 to 36 (neat times is suggesting a 63 on the wheel for proper gearing).
Can you change that 17 on the jackshaft to a smaller sprocket? If you replace the 17t to a 12t, then you can use a 44 tooth sprocket on the wheel.
Neat times is right, you are going to want about 16:1 reduction. For more reduction, make big sprockets bigger and/or small sprockets smaller. It is usually easier to use smaller small sprockets instead of using big honking sprockets on the jackshaft or wheel. The only downside is that tiny sprockets wear out faster, wear out the chain faster, and might be a bit more likely to slip a chain.
On your jackshaft diagram you are going from motor to jackshaft, jackshaft to wheel. You have 8 to 36, 17 to 36 (neat times is suggesting a 63 on the wheel for proper gearing).
Can you change that 17 on the jackshaft to a smaller sprocket? If you replace the 17t to a 12t, then you can use a 44 tooth sprocket on the wheel.
Neat times is right, you are going to want about 16:1 reduction. For more reduction, make big sprockets bigger and/or small sprockets smaller. It is usually easier to use smaller small sprockets instead of using big honking sprockets on the jackshaft or wheel. The only downside is that tiny sprockets wear out faster, wear out the chain faster, and might be a bit more likely to slip a chain.
BTW, you said your using a 20-inch wheel, right?
If your sprockets are 8 to 36, 12 to 44, then you'd do about 21mph at 6000 engine rpms. That would probably be a good balance of torque and top speed for a 49cc. Not that I have any experience with those motors, I'm just ASSuming.
If your sprockets are 8 to 36, 12 to 44, then you'd do about 21mph at 6000 engine rpms. That would probably be a good balance of torque and top speed for a 49cc. Not that I have any experience with those motors, I'm just ASSuming.