DoodleBug Performance Jackshaft
- Thread starter ProMod
- Start date
- Tags doodlebug jackshaft performance
ut:... but cool!:thumbsup:
ok, I received and installed my JackShaft kit. The quality surprised me and it went on in 10 minutes flat. Adjusting the chains another 5.
I now have a bike that can carry my 220lb carcass around some pretty impressive rocks, dirt, logging trails, etc etc etc etc.. Wow! Worth every penny. I live with a yard that has some bits that are about 30 degrees and it won't quite get me up some of them so I'm going to go for a different sprocket with a 22-24t secondary (?) to get me going up those last steep bits.
This kit is amazing and brings the bike from an un-rideable questionable purchase to an afternoon-eating lot stomper! Well done and thank you for the value.
I now have a bike that can carry my 220lb carcass around some pretty impressive rocks, dirt, logging trails, etc etc etc etc.. Wow! Worth every penny. I live with a yard that has some bits that are about 30 degrees and it won't quite get me up some of them so I'm going to go for a different sprocket with a 22-24t secondary (?) to get me going up those last steep bits.
This kit is amazing and brings the bike from an un-rideable questionable purchase to an afternoon-eating lot stomper! Well done and thank you for the value.
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Just added the J/S kit to my wifes Rivit and all I can say is WOW. This is a must do mod. It went from being useless to being fun to ride.
My Doodlebug on the other hand is getting the 7hp Preditor treatment. Got the stage one install kit from Brad when I got the J/S kit. Brad was most awsome to talk with and very helpful.:thumbsup:
My Doodlebug on the other hand is getting the 7hp Preditor treatment. Got the stage one install kit from Brad when I got the J/S kit. Brad was most awsome to talk with and very helpful.:thumbsup:
So you bought a little Doodlebugger and after your first test ride I am almost positve you were as disappointed in it's performance as I was. Anyone over 100lbs, any kind of hill or even a cruise across the lawn will leave you pedaling with your feet to keep it going. The problem....Way to high of a gear ratio for the little 2.5hp eng causing the poor little clutch some bad abuse.
The solution...
Motor swaps are cool but not for the average person. And although I love to be scared by a Hot Rod Mini Bike.(I have a Hot Rod baja heat that is making around 14hp)
A +5hp engine in one of these frames is not childs play. Even attempting to stop one fast with the little rear disc brake system will require you to add your Flintstones brakes.( scary).
Rear Sprocket changes........
I have heard you can find a larger rear sprocket blank and drill the bolt pattern to fit, But if you get the sprocket to large it will dig into the ground when turning left and has clearance problems
It just depends on how much you want to gear it down.
We have found that a 8.86 to 1 ratio works great with the little 2.5hp eng and with that can offer some suprising performance with the stock engine.
Our Bolt on Jackshaft Kit will allow the engine to actualy rev out to a RPM where it can produce it's rated horsepower and also drasticaly improve clutch life. At 225lbs I can do 27mph on flat ground and climb hills the little bike would never of dreamed of with the stock gearing.
This kit is a major upgrade for those of you that want to keep things simple and turn the little bike into something fun that Dad and kid alike can enjoy!
Mini On !
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so I have a 6.5 horsepower predator motor on my Baja mini bike. I bought a stage 2 hop up kit from nr racing. Comes with bored Carb performance air filter I also have a dual exhausting it I will show pics soon. What I'm wondering is what exactly what I need to upgrade the jack shaft on this motor on my bike? Or would I be better off just getting a different sprocket. I'm okay with motors but this stuff confuses me a bit. Bcuz no one has actually explained it. I'm looking for another cheap upgrade on my bike I'm wondering if jackshaft orr a sprocket change or maybe a billet rod or something would be better?? Please let me know.. give me details too please on exactly what to buy it would be much appreciated
I guess Ill put my "review" and experience with this kit here.
1. I ordered from hotrodmini bike, thought I had read something about free shipping or other discount in this thread and put my username in the order comments. Didnt get a discount.
2. Ordered on a wednesday, got it monday - kinda surprised it didnt come on saturday since USPS priority mail is supposed to deliver saturday and that was the 3rd day.
3. Directions referred to a included guide that was missing.
4. My clutch was stuck - very stuck.. before ordered I looked on the site for directions to prep my bike ahead of time for the new parts and there was nothing.
5. Email hotrodminibike support which provided some help knowing that nothing else should be holding the clutch on.
6. Had to buy a $15 gear puller from HF which worked - but destroyed the clutch. There was no way the clutch was coming off without damage based on how hard it came off.
7. Ordered another clutch from hotrodminibike paid another $14 for shipping. Ordered a new crank shaft bolt kit as well.
8. Kit came monday again instead of saturday in a bulging USPS small flat rate box ($5.something to ship, not $14.)
9. Bolt kit missing washers which the website said were included.
10. One of the masterlinks was defective - it was impossible to remove open it up, and once I did get it it didnt fit back together - sizing was wrong or something, no extras on a $0.10 part included.
11. Install went fine from there.
Impressions:
1. Much much faster acceleration. 0-top speed in ~5.5 seconds vs. a full 10 seconds before. (150ibs)
2 Much much lower top speed. Top speed went from 32mph to 27mph. 5mph decrease.
3. Accelerating is more fun, but cruising is less fun. Once you hit top speed, you know. Before it would gain slowly and then hit a sweet spot in the RPM range and pickup speed quickly. It is nice to maintain top speed up small hills.
4. With the clutch on facing the other way, it is very hard to oil and clean the clutch now.
5. I think the transmission noise is louder than my exhaust now. 2 chains, 2 more gears... more noise.
6. Kit pieces feel very sturdy, strong and built to last.
Total cost?
$215
Worth it?
No. I can get the predator 212 for $90 and a new clutch/chain for less. More for my money and more reliable and fun. The decrease in top speed is VERY noticeable and the videos online show the stock engine vs. the jackshift kit AND other work done.
Had the website contained directions which I looked for before buying so I could make sure install would go smooth I would have decided to just stick with a new chain which is all I really needed. Or I could have at least ordered the clutch with the kit to save on the flat rate shipping cost. Or just get a bigger engine...
Im not super experienced in this stuff, but I have installed short throw shifter/bushings, exhaust, cold air intake, rotors, calipers on my car and regularly do downhill/mtn bike maintenance.
1. I ordered from hotrodmini bike, thought I had read something about free shipping or other discount in this thread and put my username in the order comments. Didnt get a discount.
2. Ordered on a wednesday, got it monday - kinda surprised it didnt come on saturday since USPS priority mail is supposed to deliver saturday and that was the 3rd day.
3. Directions referred to a included guide that was missing.
4. My clutch was stuck - very stuck.. before ordered I looked on the site for directions to prep my bike ahead of time for the new parts and there was nothing.
5. Email hotrodminibike support which provided some help knowing that nothing else should be holding the clutch on.
6. Had to buy a $15 gear puller from HF which worked - but destroyed the clutch. There was no way the clutch was coming off without damage based on how hard it came off.
7. Ordered another clutch from hotrodminibike paid another $14 for shipping. Ordered a new crank shaft bolt kit as well.
8. Kit came monday again instead of saturday in a bulging USPS small flat rate box ($5.something to ship, not $14.)
9. Bolt kit missing washers which the website said were included.
10. One of the masterlinks was defective - it was impossible to remove open it up, and once I did get it it didnt fit back together - sizing was wrong or something, no extras on a $0.10 part included.
11. Install went fine from there.
Impressions:
1. Much much faster acceleration. 0-top speed in ~5.5 seconds vs. a full 10 seconds before. (150ibs)
2 Much much lower top speed. Top speed went from 32mph to 27mph. 5mph decrease.
3. Accelerating is more fun, but cruising is less fun. Once you hit top speed, you know. Before it would gain slowly and then hit a sweet spot in the RPM range and pickup speed quickly. It is nice to maintain top speed up small hills.
4. With the clutch on facing the other way, it is very hard to oil and clean the clutch now.
5. I think the transmission noise is louder than my exhaust now. 2 chains, 2 more gears... more noise.
6. Kit pieces feel very sturdy, strong and built to last.
Total cost?
$215
Worth it?
No. I can get the predator 212 for $90 and a new clutch/chain for less. More for my money and more reliable and fun. The decrease in top speed is VERY noticeable and the videos online show the stock engine vs. the jackshift kit AND other work done.
Had the website contained directions which I looked for before buying so I could make sure install would go smooth I would have decided to just stick with a new chain which is all I really needed. Or I could have at least ordered the clutch with the kit to save on the flat rate shipping cost. Or just get a bigger engine...
Im not super experienced in this stuff, but I have installed short throw shifter/bushings, exhaust, cold air intake, rotors, calipers on my car and regularly do downhill/mtn bike maintenance.
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