what did you do to your motorized bicycle today?

Greg58 said:
Hey General aren't you leaving out one gear? It all depends on the sprockets that are available, if the jackshaft sprockets are the same a bigger rear wheel sprocket will give more bottom end, a smaller clutch sprocket does the same.
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Youre right its 11 on the clutch to 22 teeth on jackshaft ..then 13 on other end of jackshaft to the 62 on the rear wheel. Is this a good ratio?? And can i still get bottom end power best by changing the 13 to a 15 tooth?? Thanks!
 
5-7HEAVEN said:
Like Greg mentioned, you omitted the second jackshaft sprocket.
The cheapest way to gain more low end is to change the 13t to a 15t or larger sprocket.
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Yes i ommitted the 22 tooth. It goes 11 on clutch to 22 tooth on jackshaft with a 13 tooth on other end of jackshaft %o 62 on rear wheel. Would the way u mentioned still work best?? And do i have an "average" ratio already?? Thanks!!
 
TheGeneral1 said:
Yes i ommitted the 22 tooth. It goes 11 on clutch to 22 tooth on jackshaft with a 13 tooth on other end of jackshaft %o 62 on rear wheel. Would the way u mentioned still work best?? And do i have an "average" ratio already?? Thanks!!
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Now that I know what sprocket you'd omitted, I would not recommend switching the 13t to a 15t sprocket.
Presently, you have a 9.54:1 gear ratio.
Unsure of YOUR needs.
The biggest question is if you removed your engine's governor or not.
This article should help you immensely:

http://www.affordablegokarts.com/99cc-predator.php
 
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5-7HEAVEN said:
Now that I know what sprocket you'd omitted, I would not recommend switching the 13t to a 15t sprocket.
Presently, you have a 9.54:1 gear ratio.
Unsure if that's average for your engine and bike's needs.

Let me do some researching....
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Ok great..thanx. Today my problem is..(lol).. after replacing the clutch and the clutch sprocket to jackshaft length of chain yesterday..which proved to be a lil tougher than i expected..i took it on a quick test run and after 10 days of the bike sitting without being started it died on me after going 1 block. Now for the first time it wont fire up and i cant imagine why. As far as I can figure it wouldnt have anything to do with the clutch replacement. Im hoping its going to be easy to track the problem down!
 
5-7HEAVEN said:
Now that I know what sprocket you'd omitted, I would not recommend switching the 13t to a 15t sprocket.
Presently, you have a 9.54:1 gear ratio.
Unsure if that's average for your engine and bike's needs.

Let me do some researching....
Click to expand...
My engine is a 99cc 4stroke and i weigh about 310lbs. and it actually pulls my weight rather well just not on big hills wuhich is why im hoping for more low end power.
 
TheGeneral1 said:
Ok great..thanx. Today my problem is..(lol).. after replacing the clutch and the clutch sprocket to jackshaft length of chain yesterday..which proved to be a lil tougher than i expected..i took it on a quick test run and after 10 days of the bike sitting without being started it died on me after going 1 block. Now for the first time it wont fire up and i cant imagine why. As far as I can figure it wouldnt have anything to do with the clutch replacement. Im hoping its going to be easy to track the problem down!
Click to expand...

Do you have a spark at the plug?
Do you have fuel at the carb?
 
In the article I pasted, the poster's bike is geared at 12.12:1.
To get close to 12.12:1, change your 13t to a 10t sprocket.

(22/11) X (62/10) = 12.4:1.....
(2) X (6.2) = 12.4:1.....

It's close enough, and the cheapest and easiest change to get near 12.12:1.....

If no spark at the plug, check the gap at the CDI.
Unsure of the 99cc engine's gap. Maybe the thickness of a business card.
You'd have to Google that part.
 
5-7HEAVEN said:
In the article I pasted, the poster's bike is geared at 12.12:1.
To get close to 12.12:1, change your 13t to a 10t sprocket.

(22/11) X (62/10) = 12.4:1.....
(2) X (6.2) = 12.4:1.....

It's close enough, and the cheapest and easiest change to get near 12.12:1.....

If no spark at the plug, check the gap at the CDI.
Unsure of the 99cc engine's gap. Maybe the thickness of a business card.
You'd have to Google that part.
Click to expand...
Thanks much for your help 5-7 !!
 
Good luck, General!

Someday, I'd like to do a 99cc Predator build.....
and run that power thru a shift kit!
 
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Due to an non-bicycling accident, I'm mostly house-bound.
I'm taking measurements on motor mounts' placements, plus fabbing the exhaust head pipe on my twin-engine build.

Mulling over my cordless drill starts.
 
made some headlight mounts,dont know if i like them,a floating headlight?
20170624_200953.jpg
 
Put my new side cover on and she wouldn't fire up afterwards. Would pull the rope and it would rip right out of my hand. Did some internet research before going out to troubleshoot and decided there might be something out of adjustment with the valve lash. Took off the cover and OUCH!! got everything put back and re adjusted and runs like a champ again phew
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I installed my new 3d motorsport clutch and chain tensioner guard i made. Had to re gear it back to 11.11.1 where I originally had it. Its still hard to get going without stalling so I don't know if I'm going to keep this on. It really opens up the power on this engine though. Its a very nice product. I'll give it a week and see if it grows on me otherwise I'll put it up for sale
20170624_203025.jpg


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I modified the clutch handle to be spring actuated. Much more user friendly than how it came
20170624_203054.jpg
 
I purchased Dax's rear 3/4 gallon fuel tank and rear rack a few months ago:
http://thatsdax.com/ENGINE_KIT_PARTS_PAGE_2.html

When it arrived, I didn't like the fact that the fuel petcock is located at the furthest end of the tank. It's sticks out like a sore thumb. The fuel line is vulnerable to being damaged by some opportunistic vandal.

Disappointedly, I let the tank sit. I almost sent it back to Dax.

After mulling over it for a long time, I had an idea.

I reversed the tank in its mounting rack/carrier.

The petcock and gas cap are now towards the front, right behind the seat. This tank's original mounting brackets are not perfectly matched to this fuel tank. I simply tweaked them a bit to reverse-mount the tank.

Now the petcock is 12" closer to the engine, 1/2" above the right seat stay. It's in a much better, protected position.



The rack's cross-brace was now situated directly above the gas cap, so I hacksawed it off.


upload_2017-7-2_14-53-25.png





I also installed a locking gas cap similar to this:
http://www.partsforscooters.com/134-15-Gas-Cap?sc=31&category=133063

The tank's lip just had to be filed a few millimeters for the cap to fit perfectly.

I like the Dax tank MUCH better now, since I reversed it in its mounting rack/carrier.
 

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I did nothing to mine today, other than do a 20 mile ride. About 2 miles from home on the way back, I found this in the middle of the road. I now realize that I should add some type of 'carrier' to the bike.....lol
 

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It's a glasspack. Carbon fiber on the outside. Entire exhaust pipe is very light. Already repacked it once... sounds great
 
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