Track Tac

norm clutch springs

S

subbietjw

Member
for those that run norm ge clutches what clutch spring are you using for 3-3200rpm lock up? I went by the chart they had and my lock up was way too high... using a 18t drum with light shoes... by there chart the purple spring should have been right there...
 
Purple springs should get you where you want to be if I remember right, is that what you have now? If you have white springs also, try one purple and one white. The blue springs used to be 3000rpm I think, then purple was the next step up. White is what some of the JR's use around here and I think they are for about 2700-2800 engagement. How is your shoes setup? For gradual engagement or rapid engagement?


You have the light shoes, so the engagement is higher than it would be with heavy shoes. If you need any extra parts for your clutch let me know, my teammate has a couple sets of the shoes for them as well as a couple drums and extra springs and stuff, may be a complete clutch in there...he would sell it all pretty cheap if you want them. Its all just in a box in his trailer and he has a new clutch he uses now.
 
I'm in the same boat. I found two different charts with varying rpm readings so I just ordered up a range of springs and will swap out to find the right engagement. I have an extra GE with the heavy shoes so whatever doesn't work on the light shoes will go on the heavy.
 
if you want 3-3200 your light shoes are part of your problem. you want heavy with a purple and an orange spring in position 3. it doesn't matter which side you put either spring
 
I dont think they slip less, but they could possibly help with more positive engagement since the heavier shoes should hold their lockup better and wont overheat as easy in my opinion. The light shoes get hot too easy from my experience with them, we always used the heavy shoes only
 
I prefer using the heavier shoes no matter the situation because they do lock up more positive. The noram chart isn't even close to right. Go with riekens for approximations.
 
W5R said:
I dont think they slip less, but they could possibly help with more positive engagement since the heavier shoes should hold their lockup better and wont overheat as easy in my opinion. The light shoes get hot too easy from my experience with them, we always used the heavy shoes only
Click to expand...
Pete Muller once had an article on his website explaining why heavier shoes with stronger springs worked better than lighter shoes with weaker springs. What may surprise you is; the advantage to the heavy shoes, strong spring clutch, is it holds better on the top in, and maybe in midrange. He showed the math that explained this.

If the lighter shoes do indeed get hotter while the clutch is slipping, that's a heat loss which means a power loss. Heat is a power loss, meaning less power to the rear wheels.
 
well I know 2 things!!! 1 purple springs and light shoes didn't work... 2 red springs and light shoes was quite interesting... first test I ran the hard lock up n it hit n slipped so hard I thought I had a bolt scraping the ground!!! tried the middle setting and still had the same prob but my rpms went sky high... hitting almost 5k getting going and then dropped to 3300 when full lock up hit.. so that's a no go!!! have to order the heavy shoes n the rest of the springs I don't have n re try... I think the light shoes would hit but not have the momentum to hold then release making it jerk so bad? idk more testing to come... I do know... I hope I don't regret selling my max torque with bully conversion at the end of this... well see?
 
if you cut the heavy shoes it will jerk like that also untill you run them a couple times.first time I ran with the shoes cut I pulled in because I thought I broke my chain
 
right! I thought the flywheel came loose or something!!! ive run this clutch once be for but it was on an s/a motor... n it didn't act like that... I know these clutches work good but gust got to play with it tell I get it right..
 
Tim, are the springs your using old springs or new ones? Springs do wear out over time, especially after years of abuse like some of those clutches get, when the springs are worn out the engagement wont be where it should be if you are going by the rpm the chart says it should lock up. Just something to keep in mind. If it ran better on a s/a engine then its likely just a matter of getting the right spring and weight position for what your using now.
 
When they hit and jerk like that I spray wd40 inside drum then heat cycle with throttle and brake to dry, problem gone and works perfectly.Ours was hitting so hard I thought the chain was going to break. We also only run heavy shoes.
 
Last edited:
One thing I see is, some have different phrases, words, to explain different things. It sometimes gets confusing, for me anyway. So what's new?

These are the terms I use;
when I 1st hit the throttle, and the engine is being held at some RPM, and that RPM is more than the axle is turning, divided by the gear ratio, I call that stall. Meaning the clutch is holding the engine at some RPM, and the axle rpm is less than the engine RPM divided by the gear ratio. To me, lockup is when the engine RPM, divided by the ratio, is the same as the axle. If you have a 4/1 gear ratio, when the engine is turning 4000 RPM, if there is lockup, the axle would be turning 1000 RPM. If you have the clutch adjusted to where it is holding the engine at 3600 RPM, it won't be locked up until the axle is turning 900 RPM. As you pick up speed those numbers will increase. As the axle rpm increases, the engine RPM will increase, but you will not necessarily be at lockup. The Delta, (the rpm difference between the engine and the axle) should get smaller and smaller as the kart goes faster and faster. You should never see, (feel) a decrease in rpm as you accelerate. Sometimes, if things are not right, you might see a drop in rpm, feel the clutch lockup, and then you accelerate. This should not happen. If it does, it could be caused by the engine going a little lean, or the clutch getting a little too hot. When things are right, you very seldom feel the point where the clutch locks up. It should be a very smooth transition from where the clutch shoes are slipping to where they are locked up. (Engine spinning at the same rpm as the clutch drum) Of course there is always a little slip, but it's small.

I hope that makes sense. lolo
 
I ran those clutches yrs. ago, and they are truly a big pain, I'm sure that are much better clutches available today, unless the Noram is required for your class. I had much better luck with the lowly Rev-Grip.
 
w5r - yes new springs and shoes... al nunley- I count stall as anything under the time you start to move... and full lock up as when the clutch and your motor are at a full engagement
 
I don't have them yet all the springs I have right now are heavy red, brown, green, light red, purple, orange, and blue... but I only have light shoes...
 
You must log in or register to reply here.
Back
Top