Vc 460

[David Maner]

Originally Posted by Rooster59

Does anyone know what rollers and springs come in the VC 780R clutch? It might help to know if you want to tune the clutch somewhere in between "as delivered" and the settings that David came upon.

The rollers and springs could be special size/weight. I have found elsewhere on the net where roller weights were available other than those listed on the QDS Baja matrix.

http://forums.bajasae.net/forum/uplo...SAECatalog.pdf

If you call Don Jackson at Comet and tell him what you have and where you want to be he'll tell you what weights and springs to buy..

I seem to think my 780 had blue springs and 86 gram weights as it came from VC

1 608 774 0481 is his number


ETA: The weights in my 780 as it came from VC was 68 Grams, not 86. The springs were Blue
What I have in my clutch now is 106 weights with green springs for a take up of 1100-1150 and fully shifted at 2400-2500 with tranny in neutral. I can shift from forward to reverse no problem and my idle is in the 950 to 1000 rpm range. Have no idea on the fully shifted other than with the tranny in neutral because I have no way of monitoring the clutch under motoring conditions.

When it warms up some I'm going to call Don and see if I can get my take up down closer to the 1000 rpm but remain with the 106 weights.

First thing I did was leave the original weights in my clutch and put the red springs in it and I loved it on the lower end but decided I wanted to shift out sooner so thats when I made the change to the heavier weights and green springs. Mr Jackson is who told me what to buy


Here in a bit I'll go look and see and if they were different I'll post it here

I bought my weights and springs at https://www.mfgsupply.com/301759a-10...eight-kit.html
This link is to the 106 gram weight arms/rollers I put in mine


The thing with Mfgsupply they shipped the same day. 2 days after ordering my parts they were in the mail.
I ordered the red springs the first time then I decided I wanted to shift out at a lower rpms so then I called Don again told him what I wanted to do he gave me the numbers then I called mfgsupply and ordered them. Paid with debit card

Can't go wrong with mfgsupply or Mr Jackson at comet

[Rooster59]

Thanks David. If I were going to use my cart just as a cart I would jump straight to your clutch settings. As it is, I expect to use it as a stand alone cart a lot of the time, but will also pull a modified Marathon as a seating trailer with two people on it during the warm months. That extra weight combined with hilly roads might require me to be a little more conservative with my engagement RPM and shift out RPM. I may need something in between "as delivered" and your setup.

But the parts sources will be invaluable because I feel certain I will change the RPM settings. Just not sure how much at this point. First it has to warm up so I can install that beast!

This is where I am headed.......

[David Maner]

I have the 460 and you're going with the 625. I think that the same springs and weights as I have in mine would work for you too as I'm not at a loss for take off even in the middle of a 20 degree hill plus your engine is a torque monster compared to mine and mine is no slouch.

Anyways talk to Don Jackson and he'll be able to fix you up.

Springs were 15 bucks give or take a few cents and 10 bucks shipping so if it takes a couple tries, like it did for me, it won't break the bank. Easy peasy to change the weights and springs too. I did it with the clutch still on my cart as I didn't want to unbolt the engine and the exhaust so I just laid on my back and went to work. Took all of 30 minutes most.

Enjoy that engine, I'm enjoying reading about it.

Peace

I feel that I could go to a faster shift up and still be fine and may do that. I drive my cart on the street also and the faster It shifted up the lower my rpms would be on the street

[Rooster59]

The initial engagement RPM is probably a moot point. I might not go as low as 1100 but with that engine 1200 is probably doable, even pulling firewood trailers, etc. The shift out on the road would help keep RPMs low at cruising speeds of 18-20mph. As long as the cart can pull that people-trailer. Your shift out at 2500 might really make sense. The max torque for the 625 is claimed to be at 2200 RPM. Shifting at 2500 would keep the engine close to the sweet spot after the shift and leave some RPM yet to get to max torque.

After a couple test runs the goal should be clear.

[David Maner]

We all have different uses for our carts.
Mine is mostly for Mushroom foraging where I'm wanting to travel at a slow walking pace so the slower the engine is turning the better, less noise and less stress on my part. As it came it was taking up at 1800 rpms so here I was traveling at a snails pace with my engine sounding like it wanted to take off and fly. In goes the red springs, weakest springs btw and I loved it but after a while I noticed that at the traveling speeds going from one mushroom honey hole location to the other I was still running at too many rpms so in goes the heavier weights which if I'd kept the red springs in I'd have had take up at cranking speeds so the green springs went in with those. Now I'd like to get back to a little bit lower take up rpm like I had with the original weights and the red springs.

In other words I still have a ways to go to get where I want to be and that is part of the beauty of a modified golf cart. I love having toys that I can actually Play with

The 106 weights with the green springs with a VC460 engine as I have now is a stump pulling set you back in the seat golf cart. 30 mph at 4100-4200 rpm s churning 23 inch tires. Still have close to a couple thousand rpms to go if I really want too. I don't and won't go that fast

[sho305]

You want faster shift you should lower the preload in your secondary, it will shift faster long as you are not flooring it. You will still get the rpm when you do floor it but it will not respond as quick because it will be at lower rpm before you floor it. The secondary controls part throttle rpm more than anything, the primary controls engagement and WOT rpm. Though at road speeds you are likely shifted out all the way anyhow, mine with 22s is at 25+mph or something so rpm can not be lowered beyond that without HS gears or larger tires.

I had to lighten my pucks to get 4K rpm at WOT and make my 420 clone run faster, but it does not run 4K at part throttle of course maybe 2500-3500 depending on load. It would be a total dog at 2500 WOT, but it depends on what engine and mods you have what is best rpm for you. Mine will start knocking at 2500 WOT because of the high compression, it did that once in a while with the stock clutch.

You will be leaving a lot on the table if you shift at peak torque, even most stock lawn engines make max power at 3600. Some torque engines maybe a little lower such as stock vanguards. Most stock cart engines shift at 3600-3800 in ones I have checked. Stock 420 clone loves shifting at 3600-3800 with only airbox and exhaust mods. Most cvt are roughly setup to engage at peak torque and shift at peak hp. You only engage lower when you have traction issues, common for sleds which ramp the rpm up once you get to 20mph or something and have traction.

All that said the stock G9 clutch was so good at taking off smooth and low rpm when you used light throttle, most clutches don't want to do that they want to rev a certain amount no matter. But the G9 clutch was made for casual golf cart use and it does it very well. It appears it was so good the brand new yami clutch is a very similar design. So I know exactly what you mean when you say its not shifting like you would want.

[David Maner]

Originally Posted by sho305

You want faster shift you should lower the preload in your secondary, it will shift faster long as you are not flooring it. You will still get the rpm when you do floor it but it will not respond as quick because it will be at lower rpm before you floor it. The secondary controls part throttle rpm more than anything, the primary controls engagement and WOT rpm. Though at road speeds you are likely shifted out all the way anyhow, mine with 22s is at 25+mph or something so rpm can not be lowered beyond that without HS gears or larger tires.

I had to lighten my pucks to get 4K rpm at WOT and make my 420 clone run faster, but it does not run 4K at part throttle of course maybe 2500-3500 depending on load. It would be a total dog at 2500 WOT, but it depends on what engine and mods you have what is best rpm for you. Mine will start knocking at 2500 WOT because of the high compression, it did that once in a while with the stock clutch.

You will be leaving a lot on the table if you shift at peak torque, even most stock lawn engines make max power at 3600. Some torque engines maybe a little lower such as stock vanguards. Most stock cart engines shift at 3600-3800 in ones I have checked. Stock 420 clone loves shifting at 3600-3800 with only airbox and exhaust mods. Most cvt are roughly setup to engage at peak torque and shift at peak hp. You only engage lower when you have traction issues, common for sleds which ramp the rpm up once you get to 20mph or something and have traction.

All that said the stock G9 clutch was so good at taking off smooth and low rpm when you used light throttle, most clutches don't want to do that they want to rev a certain amount no matter. But the G9 clutch was made for casual golf cart use and it does it very well. It appears it was so good the brand new yami clutch is a very similar design. So I know exactly what you mean when you say its not shifting like you would want.

I'm running a vc460 stock gears with 23 tires. I mostly use my cart for slow speed mushroom foraging in the foot hills of the Ozarks in northeastern Oklahoma. It matters not rpms, speed or incline I'm on if I stomp the throttle it'll set you back in the seat. Take off like a scalded cat.
I've got it figured out, I do believe, that the spring between the red and the green is the black ones and will be ordering a set of them this week so first chance I get I can put them in. Should give me a take up around 1000 rpms exactly where I'd like to be. I like the engine at barely off idle as I travel in the environment I'm foraging in. This 460 has no problem with that either. its not lugging and most of all its not screaming either when I want to pick up a tad of speed on the smooth trails between the mushroom honey holes. I've got the 1-3/16 driven clutch that came with my VC 460 kit and at the present have no plans to make any adjustments to it as it seems to work as its needed. on the 10, 15 or 20ish degree hills it does just fine. I can shoot rocks like coming out of a gun barrel anytime I want. Tip the cart over backwards if I wanted too. This engine is a monster as it came from VC. I added the shaft rockers as soon as they started selling them. Other than that and a car muffler and a big azz air filter designed for upwards of a 50 hp gas or diesel engine. Drilled out and fixing to replace the main jet with the adjustable one you can get from time to time on eBay for $9.70 shipped. I have my engine tuned where when I first start it or if its not been running for an hour or so in this cool or colder weather I have to use the choke. Plug is running a nice honey colored. I'm using the Autolite racing plug, can't remember the number of it off hand but its the one that is advertised on most of the racing engine catalogs, (910X maybe). Engine starts on first compression stroke and after 30 seconds or so it will settle down to a steady idle and run all day that way.
If a carbureted gasoline engine doesn't require a choke at cool or cold start up it isn't properly tuned. It will be running rich once it warms up and nothing short of outright abuse is harder on an engine than running it either rich or lean. Neither of which I'll do.
I run my 460 shrouded too. Since VC doesn't offer the shrouds I made my own and the top one can be seen in the picture of my engine in my avatar. Or the many photos I've posted. I never run or very seldom run my engine for short burst but rather once I take off I might most times be running it for hours at all speeds from idle to 4000 or so rpms. I've never ran this engine without shrouds on it and won't under any circumstances.
In 100 degree weather the oil temp will get up to 210 to 220 if I'm pushing it fairly hard, the head temperature will be in the same range, I've seen the head temp up to 225 but not all the time, depending on how hard I'm pushing it. When its cold out the oil temp will drop 10 degrees or so same as with the head temp. the only difference is when its cold it takes longer to get there than it does on a hot day.
I'm an old man (69)who has been running air cooled engines since I was old enough to drive a go kart. Put many miles on a Cushman scooter and traded it for my first car when I got old enough to get a drivers license. Over the years I've never seen an air cooled engine ruined because of too much cooling air but I have seen many die due to someone removing the shrouds thinking they weren't needed. The first question I asked before I ordered this engine was where are the shrouds and why there aren't any on the engine. I wasn't satisfied with the answer and due to personal experience I know better and I wanted this engine in my cart. Before I ever took it to the shop to begin the install I made the top and bottom shrouds to keep that air flow over the cooling fins. I guarantee you I'll get thousands of hours out of this engine too if nothing breaks due to bad design or faulty parts of which I seriously doubt will ever be.

To each his own on how he/she wants to treat their engine, heat wise that is. Heat is an air cooled engines worst enemy. Over heated engine will be from running lean or reduced air flow over the cooling fins. Over worked can be added to that mix too but because of the CVT not too much chance of that happening. Especially with a 20 plus hp engine in a 650 to 700 lb golf cart

The Go-Kart guys who are running these engines without shrouds won' t get the run times like I expect to get. One thing they have going for them is in most cases their engines are out in the open where they get a pretty good supply of cooling air, and they're planning on opening them up to freshen them up frequently, something I have no intention of doing. Over heated rings loose their temper/tension pretty quick and once they do power drops. I'll guard against that happening to my engines

My apologies for being so long winded LOL

Peace

[David Maner]

If you'll think about it, originally the gas powered golf cart was designed to mimic a sparky

[Rooster59]

Originally Posted by David Maner

If you'll think about it, originally the gas powered golf cart was designed to mimic a sparky

You're probably right David. If it were up to me a golf cart would have a clutch pedal, four forward speeds, and reverse.

[raydhd]

Warmer and raining today so I decided it was cleaning my K&N and UNI filter day. All I can say is Wow cannot believe how much "stuff" was in my prefilters on both carts and the amount of stuff in the K&N on Vicki. Suzi's inner filter was almost spotless I think due to the fact of much less riding hours on her.