max driven clutch problems

[06chops]

i have an older maxII that had a jlo 295 2stroke in it i just replaced it with a briggs vanguard 16hp i have the right clutch on the engine but i still have the clutch on the trans that was from the 2 stroke motor when i was driving it today at full throttle i could run faster than the machine went could this be because of the driven clutch spring. The driven clutch seems to open way too fast

[Robinhood02]

it should be the other way around ,top speed is achieved as the drive clutch closes and the secondary opens , are you sure the drive clutch was closeing properly as the rpm increased ??

[racerone3]

i still have the original clutch (and spring) on the T-20's of both machines i've converted to 4 strokes. while i'm sure i'm not getting every last bit of performance out of my driven clutch with the"wrong" spring, it doesn't seem to cause me any noticeable issues either.

is your belt tension set properly? correct width belt? ...

[6X6]

The driven clutch seems to open way too fast

Is the motor bogging and not able to reach a good RPM? Or is it revving but just not going very quick? Is the Drive clutch closing all the way, bringing the belt to the top of the pulley, and finally, when the motor is off, is the belt sitting at the top of the driven, actually sitting with the top of the belt above the edges of the driven, or is it flush or recessed, because if so it's really worn or too narrow a belt, and that will make you loose "low gear" causing tons of bogging/performance issues. Also check for glazed belt, pitted or worn clutch faces (Not flat from center to outside, use a straight edge, JerseyBigFoot has pics of this in the Gallery.)

[Frymechanic]

I'm not entirly sure of the specs of the JLO, but in most cases two strokes generaly rev to 5000rpms or more. And inless the vanguard is modified it is limited to 3600rpms. Second, 4 stroke engines develop more low end torque than 2 strokes and the cluthes (both drive and driven) need rpms to engage and hadle the torque. So, different spings and possibly (if they're changeable) weights need to be changed to suit. The stock driven clutch may be waiting for the extra rpms that aren't there and therefore causing the belt to slip. Also, are you sure the engine is tuned properly for the elevation/conditons of the environment because if its not it will make your 16hp feel more like 3hp even though it may seem like its reving (this condition being to lean) and therefore not driving the clutches fast enough to achive full speed. And lastly, possibly the clutches inside the tranny might be slipping and need to be rebuilt.

[06chops]

the trans is fine it worked great with the jlo295 i got about 45-50mph out of it as for the clutches the drive clutch was brand new from comet and it was calibrated for my application the driven clutch operates fine when i have the machine in up on the lift with no resistance the wheels spin like hell but when i put the machine on the ground and try and drive it the transmission clutch (driven) doesnt fully open the belt just stays at the top im going to try a smaller belt tomorrow and see if that helps i dont understand it i had this motor on a gocart and it flew 50+mph on the GPS i know im not going to achieve that kind of speed in the max but i hope to atleast be able to go about 25-30 mph

[Frymechanic]

There is not enough HP. Check the tune. Spark plugs, carb. jets, spark (magneto ect.), new fuel, and air filter. If its able to spin to full cap. with no resistance than with, the motor just doesn't have enough to get up to speed. One way to check this is to do a full speed run down hill and see if the driven clutch peaks. If so then the motor is under powered whether under sized or untuned.

[06chops]

it does go faster down hill for about a few minutes then it slows down. But recreatives uses the same motors in their maxII's with a speed of 25-30 mph im going to try and use a tiny tach to see if im getting the right rpm's from the motor

[Frymechanic]

Its too lean. This is when the motor is not getting enough fuel in the high end. Assuming its the stock carb there should be a high end needle and low end needle marked with a L & H sometimes its just a large (high) and a small (low) needles. If it idles OK DO NOT TOUCH the low needle. If it does not idle OK the you need to tune this first. To do this start the engine and allow it to reach full operating temp. Then rev it at half throttle for 10 seconds. Allow it to idle once again. Turn the Low needle out (counterclock-wise) slowly until the engine starts to spudder. Then turn the needle in (clockwise) until it starts to bog noteing the number of turns as you turn. Now back the needle off to middle of the turns counted. E.G: 1 turn counted, then back out 1/2 turn. Now, repeat this proccess with the high needle at full throttle (in nuetrul of course) making sure everything is in working order and fresh fuel. You may need to repeat the steps a couple of times as needed because changing one needle will effect the other slightly when adjusted. Hope this helps.

[broncofiresmith]

it does go faster down hill for about a few minutes then it slows down. But recreatives uses the same motors in their maxII's with a speed of 25-30 mph im going to try and use a tiny tach to see if im getting the right rpm's from the motor

I had the same problem with the 23 vanguard I just installed in my Swamp Fox. I could walk faster then it. I put a tiny talk on it and a new governor spring from max on it and it seemed to have fixed the problem. This weekend hope to get it out and drive. Recreative Ind. said the 23 could be setup to 4000 rpm

[Jeff t-boss]

Are you sure you have a correct length/width belt? When you change a motor/clutch style, it's almost a given that you are gonna have to get a different length/width belt.

[06chops]

i did change the belt to a more common size and cheeper belt still a dayco belt and set the motor up to run that length belt

[Hammer]

T-20 pully.

it should be the other way around ,top speed is achieved as the drive clutch closes and the secondary opens , are you sure the drive clutch was closeing properly as the rpm increased ??

I am having problems with the bolt that holds the belt pully on the T-20 to my MaxIV coming loose.
Is there a torque setting or what am I doing wrong. I am new to working on the machine so I have limmited knowledge.

Hammer

[Mike]

Use some thread locker on the bolt this time when you tighten it back up.

[racerone3]

Use some thread locker on the bolt this time when you tighten it back up.

clean the threads on the bolt and in the T-20 shaft with some brake clean, and use blue thread lock. you can pick up both at any auto parts store