Power secondary spring

[sho305]

Originally Posted by smallblock450sl

Don't know what happened on your order, but the Umax spring does have the "tangs" for setting the preload (a/b/c-1/2/3/4) on the spring seat and sliding sheaves.

Oops my bad, let me rephrase that: It is 5 3/8" long not including the tabs/tangs that lock in. It does have them just like stock spring. I just wondered if anyone knew stock length if it was longer, or just stronger....just curious. Can't wait to try it, it looks beefy or the paint is thicker lol.

So I'll have a umax spring on a new cut sheave with the new style spring seat. Should work much nicer than my worn out 20+ year old secondary. All Yamaha parts so it should last a while.

[kev2504]

I just ordered a new Yamaha Power spring from cartpartsplus, and have an installation question. Is it true that these springs don't have the tabs/tangs to set pre-load? Where does the spacer go? Do I have to worry about pre load then? I could just wait until it comes, and rear the instructions, but that would be too easy.
Thanks

[sho305]

The umax spring has preload (the tangs that hook in), but most others do not. They (aftermarket) are stronger to compensate, and harder to put on lol. The spacer goes behind everything next to the trans casing. It replaces the snap ring, which will fail with more spring pressure. Then the helix (spring seat) tries to rub on the trans housing. No prelaod with a straight spring with no tangs, it works like a G1 spring or other cart that reverses the engine....they don't preload either.

I got my new secondary on (w/umax spring) but was only able to do minimal riding around with it. I like it, it works well. I got grease on the belt at first my helper put 3 pumps in it lol, so took some cleaning to get it off. Now it shifts different and I need to work on the primary a little to realize full benefits. But it does shift much better, goes faster as I was not getting full high gear, and smoother. I set it to B-2 I might lower it so it shifts out more. The umax spring took some elbow grease to get on there, not really looking forward to adjusting it again. I posted photos in my build thread in clones section.

[kev2504]

I do have a new stock spring, but my buddy's electric ez-go beat me, so I need to go faster. I have the secondary sheave holder tool, so I just need to compress the spring enough to get that on. Sounds like the ratchet strap may be the way to go. I will find out this weekend.

[sho305]

The spring will not make it faster unless you have some big problem with yours. Some strong springs cut top speed. They are mostly used for more torque with a lifted cart as big tires are the same as HS gears and make them sluggish at low speeds. More speed you need to make sure your clutch is shifted all the way out, your belt is at top of primary at higher speeds. Then you need more rpm from the engine, that means no governors. Then you either put gears in or lift and tires....some do both so they can run roads at lower rpm, not really to go faster. Note if your clutches are worn from the belt you might not get top 'gear' like I was not. I still may not be getting all of it since the primary is not in the best shape.

[kev2504]

So you think I should just put the new stock spring in it then? Save the stronger spring for when I get the lift and tires? I have a new belt coming. I figured rebuild the secondary first, then the primary.

[sho305]

It could help you, just saying it could also limit top speed. I would wait but maybe it would work fine. Most stock carts don't have an issue with torque at low speeds unless you pull cars around or similar. Stock cart running right will usually spin in dirt or grass going up a hill or such. Far as top speed if the belt is at top of primary that is all you get, you need big tires or HS gears to go faster. Engine will only rev so high and that is it. New belt might help, worn ones don't shift right. Old spring might not work that well either, but I went from old stock to umax so I don't know exactly. Anyway it pays to go over the cvt, you can lose a lot of power and sometimes speed when its not working right. Only have 9.5hp and need to make sure it all gets to the rear tires.

I just put all new secondary and it sure does shift smoother and higher gearing on top, also used a cut sheave for better take off, really helps lifted carts.

[kev2504]

Well, I installed the new Secondary parts complete with the white power spring. Been driving it around all weekend. It wasn't that bad to install. I do have a puller and the secondary holding tool. Definetly helps. I used the ratchet strap to compress the spring, which worked pretty good. You can tell the RPM's are higher at slow speeds. It doesn't go any faster, but it doesn't bog down at start up either.

I think I need to do the primary now. I noticed the belt does not ride at the top of the clutch at full throttle, while on jack stands. Will new weights in the primary help with that?

[sho305]

What kind of clutch is it? G9 style it will not work well at all if a weight breaks. If they are not broken they work until they do. My clutch is worn a lot, I had to file the top edge it went straight out figure the belt could not climb it. I am using a HD kevlar belt from cpp, it is wider that helps.

You also can't judge what it (cvt) does on stands, it reacts to load so it may work differently on the cart in use. You can use marker inside the clutches and run it, it will wear the marks off showing where belt went.

[kev2504]

It is the standard Yamaha clutch. Probably never touched since it was born. I have had it for 4 years and never touched it.

That is a great idea about the marker, thanks.
Is the belt supposed to run at the top of the Primary?