Manco Magnum Express needs work, I need advice.

[hoodedthefox]

The driven is ok on a plate but the driver (engine) clutch needs to be turned around for proper belt alignment.

Denny, I have found some guides that state if you have a yellow spring on the 40 series then both the driver and driven should be flipped outwards. In my case, I do not think I have the space for the chain to be flipped, should I just replace the yellow spring with a red spring?

 

[Fiveofastback]

If it is a 40 series and it looks like it is the belt is symmetrical not assymetrical as a 30 series is. The 30 requires flat side towards block. 40 series doesnt matter. As for brakes mechanical disc is hit or miss. Lighter slower karts they can be just ok. Bigger faster especially a 420 powered one need hyd disc. Go with a wilwood or similiar brake master use metal or braided lines. Bleeding them is biggest issue usually. Some fab for mounting required but not major. RBG has a video of a conversion. Sounds like carb might need a jet change also one linkage is fixed. Battery and charging system are not hard to solve just need to see how many charge coils are under the flywheel if its 2 sets you will be golden. If just one like most 420s come with they wont chage really at all even with good regulator. 18-24 vac off the chage coils is a good indication it has 2 coils. 25$ amazon regulator 6 wire for a boat will be best solution. Just dont need tach wire. 4 terminal key switch and a wheel mounted kill switch should get you going. Put rear up on stands and figure out the carb. Then get the brakes right cause your gonna need em. If the 420 has a header and a aftermarket filter it likely need 2 sizes up on jet. Easy job just remove carb bowl and carefully remove and replace jet from bottom of carb. Reason for jack stands prevents runaway carts. Btdt.

 

[Fiveofastback]

On to your steering
Check for wheel bearing play or worn out hubs. Spindle bolts and bushings next. Start at the wheels and work your way towards the steering shaft. Look for binding or slop. Binding is usually on steering column shaft or at the tierod connection. Tierod ends are usually cheap ball and socket so lube them then check for play while a helper moves the wheel. May have to unload front tires to see more of the play. Taller tires will help your cart turn a little better but dont go a whole lot wider.

 

[Fiveofastback]

 

[Fiveofastback]

Manco 640 big brother to your 607

 

[Denny]

Just flip the driver around is all you have to worry about. It will help with belt life and power since you have a back plate and not a jackshaft. Make sure you use a Genuine Comet belt. They last way longer and work way better. Gokart Supply has a chart to cross reference numbers or sizes.

 

[Denny]

Also add a couple of thicker washers to hold that clutch on when you flip it around. Gokart Supply has the proper washer I believe. If not BMI, MFG Supply, or one of the other bigger companies. If you do go to a rack and pinion steering system make sure the rack is all metal (except for seals and bellows). The ones with a plastic center section break easily and you loose steering. Not good if you are pointing in the direction of a cliff at speed. Also like I said look up the Ackerman Principal. Building in Caster and Ackerman will do more to help that thing turn than anything else you can do! You want a max of about 8 degrees negative caster. Yes negative! Look up Caster, Camber and Toe. You will want about 1/8” toe in. This is all proven information I have given you. Feel free to ask more questions as you need to. You do have a mig welder and can weld right?

 

[hoodedthefox]

Also add a couple of thicker washers to hold that clutch on when you flip it around. Gokart Supply has the proper washer I believe. If not BMI, MFG Supply, or one of the other bigger companies. If you do go to a rack and pinion steering system make sure the rack is all metal (except for seals and bellows). The ones with a plastic center section break easily and you loose steering. Not good if you are pointing in the direction of a cliff at speed. Also like I said look up the Ackerman Principal. Building in Caster and Ackerman will do more to help that thing turn than anything else you can do! You want a max of about 8 degrees negative caster. Yes negative! Look up Caster, Camber and Toe. You will want about 1/8” toe in. This is all proven information I have given you. Feel free to ask more questions as you need to. You do have a mig welder and can weld right?

I do not have a welder, I have approximate welding knowledge, but little hands on experience. I think I can get easy access to a fluxcore, my neighbor may have a Mig hidden.

I'm waiting for some parts to get in and a good weekend to take over the garage to address a bunch of these easier tasks. Upgraded brakes, suspension, and a new engine mount are tasks for later.

 

[hoodedthefox]

Also add a couple of thicker washers to hold that clutch on when you flip it around. Gokart Supply has the proper washer I believe. If not BMI, MFG Supply, or one of the other bigger companies. If you do go to a rack and pinion steering system make sure the rack is all metal (except for seals and bellows). The ones with a plastic center section break easily and you loose steering. Not good if you are pointing in the direction of a cliff at speed. Also like I said look up the Ackerman Principal. Building in Caster and Ackerman will do more to help that thing turn than anything else you can do! You want a max of about 8 degrees negative caster. Yes negative! Look up Caster, Camber and Toe. You will want about 1/8” toe in. This is all proven information I have given you. Feel free to ask more questions as you need to. You do have a mig welder and can weld right?

Denny,

AS far as the hydraulic brake goes, does it make a difference new or used? Is a kit better than pieces, should I just look around for a set off an atv?

Will a flux core welder be adequate for the task at hand?

 

[Denny]

Lots of people use flux core welders on here with good results.
As far as brakes go, I myself would buy new. Stay away from stainless steel discs they don’t stop good. If you buy a complete setup from one source you have a better chance of it stopping better.

 

[hoodedthefox]

Lots of people use flux core welders on here with good results.
As far as brakes go, I myself would buy new. Stay away from stainless steel discs they don’t stop good. If you buy a complete setup from one source you have a better chance of it stopping better.

Sounds reasonable, so one of the pre made kits or just source new pieces? I did pick up the hex axle 6" rotor that is slotted. I will either cut off the old flat rotor or use that for the new brakes.

 

[Denny]

Most guys have good luck with the pre made kits. Just make sure the lines are long enough. If you are building your own kit just try to get a master with a large resivor. It will be easier to bleed the brakes.

 

[hoodedthefox]

If it is a 40 series and it looks like it is the belt is symmetrical not assymetrical as a 30 series is. The 30 requires flat side towards block. 40 series doesnt matter. As for brakes mechanical disc is hit or miss. Lighter slower karts they can be just ok. Bigger faster especially a 420 powered one need hyd disc. Go with a wilwood or similiar brake master use metal or braided lines. Bleeding them is biggest issue usually. Some fab for mounting required but not major. RBG has a video of a conversion. Sounds like carb might need a jet change also one linkage is fixed. Battery and charging system are not hard to solve just need to see how many charge coils are under the flywheel if its 2 sets you will be golden. If just one like most 420s come with they wont chage really at all even with good regulator. 18-24 vac off the chage coils is a good indication it has 2 coils. 25$ amazon regulator 6 wire for a boat will be best solution. Just dont need tach wire. 4 terminal key switch and a wheel mounted kill switch should get you going. Put rear up on stands and figure out the carb. Then get the brakes right cause your gonna need em. If the 420 has a header and a aftermarket filter it likely need 2 sizes up on jet. Easy job just remove carb bowl and carefully remove and replace jet from bottom of carb. Reason for jack stands prevents runaway carts. Btdt.

Alright, I got the jet out today and it is labeled as a #97. I'm not positive but that may be stock. So is the consensus that with the header and air filter I should head up to a #99?

 

[Dingo ate yo baby]

View attachment 134130

FiveO, where can I find a steering rack like you have?

 

[rbsterli]

I believe the driven pulley, (the one with the yellow spring in it) should mount inboard. It needs flipped the other way.

No. That's why it has the yellow spring. That's called a reverse spring for this situation.