Baja 200 Upgrades

[joshw0000]

You running away issue.
Is the idle set to high and causing the driver to start engaging?
Are the pullies aligned? A little misalignment could cause the belt to drag and cause this issue. Being on the backing plate helps but you can add washers to shim it a little.

I don't believe it is. When I first crunk the bike it idled fine. It was only after riding a few miles that it pulled when I came to a stop. I'll double check tomorrow but I believe the throttle has a retention spring, which is something I usually add to any go kart / mini bike to make sure it returns fully after throttling.

I use a metal ruler to align the driver and driven plates, adding washers until the ruler lays flush across the back of both without bending. I can't say it's 100% perfect but it's very close if not perfect.

I didn't put screws in the bottom of the plastic cover and I could hear it chattering a little underneath it. Maybe the cover is causing issues.

What does the inside looks like ?
View attachment 157334

Possible to use a larger diameter bolt and drill the bore to fit?

I should have took a picture of the inside before I reinstalled it. It's basically an opening in the shape of the bolt head at the top. The bottom half is drilled the diameter of the bolt. So essentially when the bolt is dropped in it can be tightened from the bottom without needing to use a tool to hold the head of it. Adding the shrink wrap / electrical tape made the fit very tight. I used a punch and hammer to tap the bolt into place and it doesn't wiggle at all now inside of this piece.

These 2 pieces sit on top of a rubber grommet and the bolt goes through the grommet/silver cap, through the plate above the mini bike shocks, through another rubber grommet/silver cap, and is secured on the bottom with nuts. The wiggle I'm experiencing now is the rubber grommets allowing some shifting. I'm going to see if it helps to simply remove them tomorrow.

 

[joshw0000]

Thoughts on a 12T sprocket on the driven for a higher top speed? I have a 40T on the rear wheel and 10T on the driven now. I know it'll increase the top speed, but I'm not sure by how much or how bad it'll hurt torque?

I could get an 11T, 12T, or 13T for the driven. I think anything higher than that and I'd have to roll down a hill to get going. Would moving the spring to the far right hole on the driven help restore a little torque? I'm not taking it out on trails, but there are a few mild hills in my yard and I don't want it to struggle. One of my dogs is pretty fast and he's been known to pop a tire if he catches me.

Obviously, this is after I work out a couple bugs.

 

[Whitetrashrocker]

Im at a loss. Sounds like your well versed in what your doing.

If you can stand the vibrations I'd ditch the rubber bushing. Or squash the snot out of em.

A 40 tooth is a small rear. Most people shoot for 6:1 your at 4:1.

 

[panchothedog]

To fix your creeping at idle problem install a set of stronger garter springs. They're only about 10 bucks for a set and are so many strengths available that you can raise the engagement rpm in pretty small increments. I wasn't really trying to bad mouth the juggernaut, they work fine. I just don't think that they are worth 3 times the price of a stock driver.

 

[panchothedog]

The small sprockets are pretty cheap. That is clearly the way to go as compared to the larger axle sprockets. At 10 X 40 you are already geared pretty high. Try the 11 and see how you like it. At 12 X 40 I think you will struggle on hills. Does your engine still have the governor in place? I have a MB trailmaster that has the tall tires ( 19" yours look similar ) and I run a 10 X 60. My engine is built and the governor removed so it is capable of much higher rpm than a stock one.

 

[joshw0000]

Im at a loss. Sounds like your well versed in what your doing.

If you can stand the vibrations I'd ditch the rubber bushing. Or squash the snot out of em.

A 40 tooth is a small rear. Most people shoot for 6:1 your at 4:1.

My first project was trying to convert a cheap/broke Chinese go kart (the ones that come F-N-R) to a Predator. You can read about it on this forum. I had a LOT of issues and finally gave up on it, lol.

I'm going to try it. Fingers crossed it's ok.

I'm no expert, but from what I understand if I had a 6:1 on this bike, the top speed would lower but I'd have much more torque? My last mini bike (it was the smaller frame) had a 6:1 but it had a clutch, not a T/C. Takeoff was decent, but top speed felt much faster than this one. This bike came with a 10T front 50T rear cluck / jackshaft. I didn't get to test it much at higher speeds due to the issues with the jackshaft but it didn't feel that fast when I got it. That's why I swapped to the T/C and lower count rear sprocket.

To fix your creeping at idle problem install a set of stronger garter springs. They're only about 10 bucks for a set and are so many strengths available that you can raise the engagement rpm in pretty small increments. I wasn't really trying to bad mouth the juggernaut, they work fine. I just don't think that they are worth 3 times the price of a stock driver.

The small sprockets are pretty cheap. That is clearly the way to go as compared to the larger axle sprockets. At 10 X 40 you are already geared pretty high. Try the 11 and see how you like it. At 12 X 40 I think you will struggle on hills. Does your engine still have the governor in place? I have a MB trailmaster that has the tall tires ( 19" yours look similar ) and I run a 10 X 60. My engine is built and the governor removed so it is capable of much higher rpm than a stock one.

Understand completely about the juggernaut.

I moved the governor spring to the far right (under the gas tank). It's still technically governed but it revs higher than stock. To my knowledge, the engine is otherwise stock.

I like your thought process on the lower gearing (for top speed) and changing springs to help with torque/creep (or at least I think that's where you're going with it). If I went with the 11T front / 40T rear, what color garter springs would you recommend? What are your thoughts on changing the spring in the driven and/or moving it to the far right hole?

 

[Minimichael]

Just a thought on handlebars, I like aftermarket clamps for their performance. They clamp great and look great, though you may have to drill out your bike's tree mount holes to 10 or 12mm.

 

[joshw0000]

Just a thought on handlebars, I like aftermarket clamps for their performance. They clamp great and look great, though you may have to drill out your bike's tree mount holes to 10 or 12mm.

Sorry, I'm not following you. Something like this?

 

[Denny]

That’s the wiggle you’re talking about! That’s normal, helps reduce the vibration in the handle bars. Heck, my Harley even had that!

 

[panchothedog]

My first project was trying to convert a cheap/broke Chinese go kart (the ones that come F-N-R) to a Predator. You can read about it on this forum. I had a LOT of issues and finally gave up on it, lol.

I'm going to try it. Fingers crossed it's ok.

I'm no expert, but from what I understand if I had a 6:1 on this bike, the top speed would lower but I'd have much more torque? My last mini bike (it was the smaller frame) had a 6:1 but it had a clutch, not a T/C. Takeoff was decent, but top speed felt much faster than this one. This bike came with a 10T front 50T rear cluck / jackshaft. I didn't get to test it much at higher speeds due to the issues with the jackshaft but it didn't feel that fast when I got it. That's why I swapped to the T/C and lower count rear sprocket.




Understand completely about the juggernaut.

I moved the governor spring to the far right (under the gas tank). It's still technically governed but it revs higher than stock. To my knowledge, the engine is otherwise stock.

I like your thought process on the lower gearing (for top speed) and changing springs to help with torque/creep (or at least I think that's where you're going with it). If I went with the 11T front / 40T rear, what color garter springs would you recommend? What are your thoughts on changing the spring in the driven and/or moving it to the far right hole?

You are kind of talking about two different situations here. The garter springs will increase engagement rpm, but also increase the rpm that the driver fully closes, high gear. I dug out an old Comet spring chart. Stock is 1400 rpm. Orange is 1500
Pink is 1800, and purple is 2000. They put a small dab of paint on the end of the spring in order to tell which is which. 10 minutes after running them, they all look identical. Even with your governor gizmo adjustment, I wouldn't recommend more than 1800. Otherwise you might not have enough rpm to get to high range.
On moving to spring in the driven clutch, if you move it to the left counterclockwise it will not open as soon, staying in the lower gear range a little longer and providing more torque. If you move it to the right, clockwise, it will go into high gear ( open up ) sooner. Hurting torque (or punch).
My bike came with a 10 X 48. I put the 60 on there ( mathematically that reduces top end speed ) for stronger acceleration and better hill climbing ability. It is used almost exclusively off road. I don't have a tachometer on any of the stuff I own, but I would guess it gets into the 5500 - 5700 range. It will top out at 44 mph on a dirt road, and that is plenty fast for me.

 

[Minimichael]

Sorry, I'm not following you. Something like this?

View attachment 157347

Something like these, providing they fit your bar's diameter. I used to want to keep original clamps but I always found them pretty worn and unable to stop my handlebars from slipping. A fresh set of shiny riser clamps just offers peace of mind – and a strong grip.

 

[joshw0000]

That’s the wiggle you’re talking about! That’s normal, helps reduce the vibration in the handle bars. Heck, my Harley even had that!

After tightening the nuts on that hold the handle bars clamps down, I can wiggle the handlebars back and forth slightly. My Road King has a wiggle, but that's because the whole bike is shaking, not just the handlebars, lol.

 

[joshw0000]

You are kind of talking about two different situations here. The garter springs will increase engagement rpm, but also increase the rpm that the driver fully closes, high gear. I dug out an old Comet spring chart. Stock is 1400 rpm. Orange is 1500
Pink is 1800, and purple is 2000. They put a small dab of paint on the end of the spring in order to tell which is which. 10 minutes after running them, they all look identical. Even with your governor gizmo adjustment, I wouldn't recommend more than 1800. Otherwise you might not have enough rpm to get to high range.
On moving to spring in the driven clutch, if you move it to the left counterclockwise it will not open as soon, staying in the lower gear range a little longer and providing more torque. If you move it to the right, clockwise, it will go into high gear ( open up ) sooner. Hurting torque (or punch).
My bike came with a 10 X 48. I put the 60 on there ( mathematically that reduces top end speed ) for stronger acceleration and better hill climbing ability. It is used almost exclusively off road. I don't have a tachometer on any of the stuff I own, but I would guess it gets into the 5500 - 5700 range. It will top out at 44 mph on a dirt road, and that is plenty fast for me.

It sounds like I just need to stop being a wuss, open the motor and build it for more power. I want all the torque and all the top speed, lol.

Ok, I had my logic backwards on the driven spring. Left = torque, right = top end speed.

I just counted the teeth again to confirm. My stock rear sprocket has 50T.

I remember changing the garter springs, and moving the driven spring on the first go kart I built, at the recommendation of a member here. It made it absolutely rowdy on take off (burnouts on concrete), which led to me ripping my poor welds on the motor mount to the thin metal frame of the go kart and kicking chains off every time it was ridden, since things were flexing.

I guess where I'm confused, if the T/C engages at a higher RPM, does that have any negative affects on top end speed? I realize it'll potentially burnout or wheelie on takeoff if engage at too high of RPM. At least in my mind, if I gear it down (11T / 40T) and have the T/C engage at higher RPM, it should still have some umph off the line but ultimately have a higher top speed than it does now. I'm sure my logic is flawed somehow or everyone would be doing this, lol.

 

[joshw0000]

Something like these, providing they fit your bar's diameter. I used to want to keep original clamps but I always found them pretty worn and unable to stop my handlebars from slipping. A fresh set of shiny riser clamps just offers peace of mind – and a strong grip.

Ah ok, that's what I thought you meant. If removing those bushings doesn't stiffen things up, this will be my resolution to that issue, thanks.

 

[Edwin Spangler]

I guess where I'm confused, if the T/C engages at a higher RPM, does that have any negative affects on top end speed? I realize it'll potentially burnout or wheelie on takeoff if engage at too high of RPM. At least in my mind, if I gear it down (11T / 40T) and have the T/C engage at higher RPM, it should still have some umph off the line but ultimately have a higher top speed than it does now. I'm sure my logic is flawed somehow or everyone would be doing this, lol.

No loss of top speed. The trade-off for having that high-reving, hard take off is just that, you always have to take off in higher RPMs. Makes it difficult to drive slowly.

 

[joshw0000]

The handlebar grommets are now trashed and replaced with washers (and thread locked nuts). That issue is resolved.

I checked and the driver bolt had worked its way loose when I rode it yesterday. I wouldn't normally threadlock that bolt but this lug nut thing is a little easier to install/remove, so now it's thread locked.

I moved the spring on the driven over for more torque and it rode pretty well. Still no wheelies but the front will lift if I throttle and shift my body weight with it. Towards the end, it started to pull again. I could coast uphill without touching the throttle. BUT, when I checked, that nut had worked its way loose as well. So I tightened it just to the point where it would still move freely and not bind up. Hopefully it'll be fine next time I ride. If not I'll flip the lock nut around as it's only getting about 1/2 into the blue part that "locks" the thread.

I'm going to start by ordering the 11T sprocket and see what change that makes to performance before ordering any springs. I appreciate everyone's input.

 

[panchothedog]

Bigger drive sprockets ( 11 or 12 tooth ) will potentially give you more top speed, up until the engine runs out of power. Just because the math says it will go faster, doesn't mean the engine can pull hard enough ( torque ) to get there. If you really want all the torque and speed you can get from it, well then it's time to get out the credit card and order some parts. Plenty will disagree with me, but I can't stand a governed engine. Seems like such a waste of potential. Power is made in the upper rpm range. Most of my engines get opened up and modified as soon as they come out of the box. More fun working with clean brand new stuff.

 

[joshw0000]

So I installed the 11T sprocket and the pink springs. That's when I realized that 1800 RPM is less than stock so the bike took off as soon as I crunk it. I'm now running white springs and it's doing much better.

Sooo...in another thread, you can read about the $100 mini bike I got and blew the engine. Well, I've decided I'm going to take the motor (only) from this bike and transfer it to the other bike. Then I'll get a new 212 or 224 for this bike. The first thing I plan to do is remove the governor and change the flywheel to an aluminum one. I also have a brand new VM22 carb that I'll install, and I plan to rob the exhaust from the other bike.

What else should I do? I'm not looking to blow the bank here, but if it's cheap power or reliability, I'm interested.

With the VM22 carb, which jet should I use? I believe they go up to 120.

Should I replace valve springs? If so, what weight?

I'm still shopping for the motor, so I have time to brainstorm. Hopefully a brand new one pops up on Marketplace for the cheap. Or maybe HF will run a sale. I've never opened one of these engines up, but I think I'm going to have to to get more power.

 

[Whitetrashrocker]

Flywheel, stiffer springs and take a dremel to the head and open them up and match the ports. If you can, take .040 or so off the head you'll be happy.