40 Series Torque Converter config

[MTScott]

So I've searched high and low for the perfect 40 serious setup that we KNOW works well, as well as being cost effective.

Well I arrived and thinking the only sure thing was buying the comet kit; however, even that one isn't perfect, it seems. I have a hard time paying top dollar ($400 by the time it gets to my door) to buy a kit that still needs to be dicked with.

My main hang up is how the drive clutch/converter is oriented. In many setups (even the comet kit from GPS), the pictures show the clutch with the spring/weight side facing out, away from the motor. After enough searching, watching videos, and reading forum after forum I'm convinced that the proper way to install this is with the spring/weight side of the clutch facing the motor (this assumes that the spring side of your driven converter/pulley is facing out). This keeps both sheaves moving in the same direction, therefore maintaining proper belt alignment at speed. This seems counterintuitive at first because one might think that the stationary sheave plate should be on the same side, but not when you watch how the belt centers as the sheaves move in and out.

The problem with the GPS comet kit is it seems this orientation was not planned on, and you need to space the driven pulley out to make it operate this way, or flip the driven and space the drive clutch/converter out. Either way you could run out of shaft on either end.

I'm also considering the blastLED setup, but it isn't perfect either, nor is it cheap, but it does appear to have a solid quality backing plate. Other kits seem to have a flimsy backing plate.

So, I dunno, chinese or not, is there a kit out there that lines up proper???

I'm starting to think that the best way to do this, is to just buy a clutch and pulley pair, and build a jackshaft setup which allows me to adjust the driven pulley wherever it needs to be, rather than rely on a backplate kit? I'd rather just have kit that bolted on and worked, but if I have to fab more then so be it. I'm building this whole thing from scratch anyway.

Thoughts anyone? Feel free to tell me I'm wrong about everything, and generally laugh at me.

 

[madprofessor]

I'm starting to think that the best way to do this, is to just buy a clutch and pulley pair, and build a jackshaft setup which allows me to adjust the driven pulley wherever it needs to be, rather than rely on a backplate kit?

Absolutely correct, but you don't need to buy another set of pulleys. The backplate forces the mounting of both pulleys to have the spring on the outboard side, and since they work opposite each other (driver starts open, driven starts closed, then they reverse with speed) they need to be facing opposite each other. You don't need another kit, just freely mount the driver on the motor shaft, and mount the driven on a separate jackshaft that you install yourself.
Click the GokartSupply.com link below, read all of the text at the beginning, then scroll all the way to the bottom and read all of the text there, then find the B&W diagram drawing of the 40 series in between that shows you how to mount the pulleys. You'll understand all you need to know after all that.
I'll put in a link for some 40 series while I'm at it, but you should be able to use what you've already got. Regardless of how good or how Chinese (my stuff) a 30 or 40 series is, it should always get the expensive Comet belt. Cheap out on the rest if you want, I sure have.
Comet Drive Belts | Comet Torque Converter Belts | Go Kart Belts (gokartsupply.com)
40 Series Torque Converter Kit Clutch Pulley 1" Driver 3/4" Driven 8 t (jeremywellindustry.com)
1" Driver + 3/4'' 40 Series Driven Clutch Kit For Comet Go Kart Torque Converter | eBay

 

[Denny]

The Chinese I’m CVTs work as good as the Comet’s do. And you can even use the Comet parts to repair worn parts. The proper way to mount a 40 series is with a jackshaft spring facing inboard on the secondary and weights outboard on primary. And only use Genuine Comet belts! They cost more but last way way longer and won’t cause premature wear on the shieves.

 

[MTScott]

Absolutely correct, but you don't need to buy another set of pulleys. The backplate forces the mounting of both pulleys to have the spring on the outboard side, and since they work opposite each other (driver starts open, driven starts closed, then they reverse with speed) they need to be facing opposite each other. You don't need another kit, just freely mount the driver on the motor shaft, and mount the driven on a separate jackshaft that you install yourself.
Click the GokartSupply.com link below, read all of the text at the beginning, then scroll all the way to the bottom and read all of the text there, then find the B&W diagram drawing of the 40 series in between that shows you how to mount the pulleys. You'll understand all you need to know after all that.
I'll put in a link for some 40 series while I'm at it, but you should be able to use what you've already got. Regardless of how good or how Chinese (my stuff) a 30 or 40 series is, it should always get the expensive Comet belt. Cheap out on the rest if you want, I sure have.
Comet Drive Belts | Comet Torque Converter Belts | Go Kart Belts (gokartsupply.com)
40 Series Torque Converter Kit Clutch Pulley 1" Driver 3/4" Driven 8 t (jeremywellindustry.com)
1" Driver + 3/4'' 40 Series Driven Clutch Kit For Comet Go Kart Torque Converter | eBay

Okay, great info, thanks... I haven't actually purchased anything, so this is good. Set of pulleys, quality belt, and parts to make a jackshaft then (I'm thinking a couple pillow blocks, keyed shaft, some collars, and a keyed sprocket).

The Chinese I’m CVTs work as good as the Comet’s do. And you can even use the Comet parts to repair worn parts. The proper way to mount a 40 series is with a jackshaft spring facing inboard on the secondary and weights outboard on primary. And only use Genuine Comet belts! They cost more but last way way longer and won’t cause premature wear on the shieves.

So to confirm - the primary drive, on the engine shaft - the bell containing weights and springs should face out, away from the engine.
On the driven pully, the spring side should face the opposite direction, inward, towards the engine.

What is surprising to me, is that so many plate kits exist out there, and plenty have been installed, yet none of it seems like a proper solution...???

Thanks gents

 

[MTScott]

So this kit actually looks like it'll line up proper with the drive pulley reversed:
Amazon Chinesium Kit

One review though, says that flipping the drive pulley requires the idle to be lower, or something.

What are the negative affects of reversing the drive pulley/clutch?

 

[Denny]

With the back plate you need to make sure it has the reverse wound spring and the belt alignment is still off a bit.

 

[madprofessor]

Don't get confused about the 30 and 40 series. The 30 series for up to 8hp. is what you see advertised the most, and they are made from the start to work on a backplate. It's because they're asymmetrical with belts having one side flat, instead of like your 40 series which is symmetrical using standard V-belts.
30 series absolutely must have both pulleys facing the same direction, with their flat sides in perfect alignment against the backplate.
I personally wouldn't ever build with a 40 series that I didn't build in perfect alignment, with the pulleys facing in opposite directions. The options against that just bother my OCD terribly, constantly moving in/out of alignment.
Cast Iron Pillow Block with 3/4" Bearing | 999220 | BMI Karts And Parts
3/4" Keyed Shaft | 400134-** | BMI Karts And Parts
3/4" Bore Double Split Shaft Collar Black Oxide Set Screw Style (4 PCS (jeremywellindustry.com)
Slapping on a jackshaft is so very easy.