Hisun Axis 500 Speed limit

[Sylvain Gravel]

Hi,

Is there a way to speed up my Hisun Axix 500? With the seat  buckle up, the top speed remains to 28 or 30 MPH.  I have seen there's a speed limiter module right in the middle under the hood. This unit it is a must for the functionality of the vihicle. May be there's some way to hack this device. 

 

 

Thanks!!

[aefron88]

The speed limiter box only limit speed while running in reverse to prevent cutting the wheel over at high speed and rolling your utv.

I'm not familiar with the 500, but you should be able to do slightly faster than that. I've had my 400 up to 35 (indicated) and it wasn't quite at redline yet.

[kgs]

I would think it should go a little faster but not much, I got a hisun 550 sector which has a different motor then the 500 but I can get it up to 45 before the limiter kicks in and has it cut out, that's so you don't blow your motor up. 

[aefron88]

KGS just to be clear, since the question is about the speed limiter relay:

The max speed is controlled by the gear ratio of the belt on the primary/secondary clutches.

The max engine rpm is controlled by the Delphi MT05 ECU. It is technically adjustable, but it is set to be a safe limit to prevent blowing up the motor.

The speed limiter relay kicks on when the shifter is in reverse to limit the max speed. This is an add on by Hisun because there is no gear input for the Delphi ECU, which is designed to be a flexible, cheap fuel injection solution for a variety of small engines.

[Sylvain Gravel]

Thanks all of you for the answer.

[Greg Kilgore]

My 2022 Axis 500 can get about 30 MPH in low and 41 MPH in high. 45 + MPH down hill.

 

Has about 62 hours. 1082 miles. All stock. Except I did put in 4-point harness for driver and passenger. 

[Alex]

Added manufacturer and model to topic title 😁

[Brent]

There appears to be a couple of experts here and had a question not related to speed but gearing. Is there a way to change the gearing ratio to improve torque? I have an Axis 500 and use it for launching a boat in a small lake on a gentle slope. It will pull it out but if one side of the trailer gets stuck, the engine just Boggs down in low; even in 4 wheel and locked differential. I would have thought the rear wheels would at least spin.

[aefron88]

Basically replacing the clutches with something non standard, or putting smaller tires, so more or less not practical to change gearing.

Keep in mind these things just don't make a lot of HP and the trailer might be too much to haul around. I would expect it will effect the clutch life significantly towing the trailer around.

[Greg Kilgore]

Brent, 

The Axis has a wet clutch and then a belt.

If the engine is running then the clutch is spinning. There are paws the sling outward on the clutch that engages the clutch drum. There's not a lot of friction material on the paws.

 

The clutch drum has a shaft. That shaft spins the primary sheave. The primary sheave spins the cvt belt. The cvt belt spins the secondary sheave. The gearing is determined by how Hi or low the belt rides on the primary and secondary sheaves.

The primary sheaves has weights that will move outward so the space between the inner and outer section of the primary sheave varies so the belt can move up and down. 

Same thing happens on the secondary sheave except it is controlled by a spring.

 

If the engine is running, machine running and in gear. And machine isn't moving. Either the wet clutch or cvt belt is slipping.  Either is bad. Usually if the belt is slipping there is usually smoke and a smell. 

 

The weights in the primary sheave and spring in the secondary can be changed. This changes how the cvt belt travels up and down the sheaves and the gearing.

 

I don't know enough to tell you how to change the weights or spring for better performance for what your needing. Just kinda the basic operation. 

 

I have read on other boards about a spacer between the outer primary sheave and nut. That will lower the top speed a little to give a little more torque when riding up hills. But for what your needing I'd say it probably a combination of weights and spring in the sheaves.

 

Now most important thing. I'm no expert. And I may have explained things completely wrong. If I'm wrong someone let me know and I'll delete this post. I don't want to spread misinformation or point people in the wrong direction.

 

Brent, start your own post if you decide to tackle the pulling issue you have. I would like to know your solution. I live 10 minutes from the lake. And 15-20 minutes from 3 different boat ramps. I would like to take my Axis 500 and launch a boat. (Have 3. 16ft pontoon 25hp, 15ft bass 110hp, 14ft V bottom 5hp.) There's also a few places that I could launch, not a ramp, just the shore but I'd have to back out into the lake a little more that I like. And don't want to get stuck or sink up. 

 

Good luck.

[aefron88]

Greg's post is exactly right on the technical details. Unfortunately there aren't different springs and weights available off the shelf for these models so you would have to experiment. There are people with expertise adjusting belt drive clutches, primarily in snowmobiles, who may be able to male a good guess on what you need and identify compatable parts.

Unfortunately these belt driven vehicles don't do a good job towing heavy weights, because they're always subject to slipping, and ontop of that a lot of people report wear issues with Hisun wet clutches anyway.

[Brent]

Greg & aefrn88,

Appreciate your advise.  I may just live with it for now and really don't want to get into the engine since I'm not an expert mechanic. it only happens when one trailer wheel gets in a rut.  Last time it happened I just backed down a little and got a running start. 🙂  

My situation is with a primitive landing that I built so I can repair where needed.  I have a Boston Whaler 14 Ft with a trolling motor on front.  I took off the gas engine since I'm not allowed to use gas on this particular lake.  It helps make it lighter too.

[aefron88]

One thing you can do is swap to snowmobile trailer tires, which are wider and will float over soft spots better. That's the setup I have on my sailboat trailer.

I have two Boston whalers also (a 15 classic and V-20 Revenge), but those both get launched on concrete ramps.

[lincolnsq175]

Theres a few things you can do to get more torque. You can shim the primary which will give you more torque but takeaway some top end speed. You couls also slug wet clutch which will make the wet clutch grab quicker and harder. Than the best mod but expensive is jbs machined sheave kit which will give you morr power everywhere. You can also i install an epi clutch kit with different weight rollers and secondary springs. Clutch parts for a yamaha rhino 450 fit.

[Sylvain Gravel]

On 2/5/2023 at 5:35 PM, lincolnsq175 said:

Theres a few things you can do to get more torque. You can shim the primary which will give you more torque but takeaway some top end speed. You couls also slug wet clutch which will make the wet clutch grab quicker and harder. Than the best mod but expensive is jbs machined sheave kit which will give you morr power everywhere. You can also i install an epi clutch kit with different weight rollers and secondary springs. Clutch parts for a yamaha rhino 450 fit.

Thanks for the tips.