how to increase mph without swapping engine?

[Byrd]

I have a hustler 950 with a fairly new Briggs 14hp engine and I'm wondering what I can do to squeeze out some more mph without swapping out the engine?she is slow ,maybe 8 to 12 mph and I would like 20ish if possible.
Different clutch, gears,belt or combination of all?thanks for any suggestions. :-)

[Mike]

If you had a higher HP engine, then you could stand to go with some higher geared sprockets because the torque from the motor would make up for what you lose in gearing but with the 14HP, I would be hesitant to change the gearing. Also, for the couple of teeth that you would most likely change, you really wouldn't gain that much of a difference in your top end. Most of the clutch changes that you see here on the forums involve changing the springs out which adjusts when the clutches engage but not the final ratio. There are some clutches that will give you a higher top speed but it's probably not enough of a gain to make it worth it either. Your real limitation with speed is the RPM that your engine turns and that is limited by the governor. You can adjust or remove the governor and probably see your largest gain in top speed but you will need to make a few upgrades to the engine when you do and you will still have to be conscious of how high you are revving it. Search the engine forum for more info.

[Noel Woods]

The little 14 hp would be only just adequate for a 950. My tan Max2 started out with a 14, but when compression really started dropping I figured I had about 10hp, and switched that engine out with an 18hp and that made for a totally different machine. There are several other options out there, duromax makes a single cylinder 16 hp for less than $300, so for not a lot of money you could get a nice little power plant. Here's their link:

http://www.maxtool.com/index/DuroMax_engines/pm16hpe.asp

My theory is the 14 you have is on the way out anyway.

[jpswift1]

The 14HP Briggs Vanguard can be easily upped to 16HP by simply swapping a 16HP carburetor and taking the little exhaust restrictor rings out with a pair of pliers......simply unbolt your exhaust manifold and you'll see them in the heads. The 14HP will move a 950 rather well, and the 16HP upgrade will work great for you. A stock Hustler 950 4 stroke should run at least 20mph, maybe even up to 25mph.

I'd say before you pull engines or mess with gearing, start by making sure your drive belt is not worn or too lose but not super tight and not worn. That's a very common issue that'll make the machine go slow. Also, check your drive and driven clutches to make sure the parts aren't worn and they're both opening up properly. Get back

[Tomo]

hi
U need an increase in hp/torque first and then a RPM increase
Remember if u gear the 6x6 hard [to tall 4 speed] the loss could be significant at the bottom end . As mike has already stated .
If u try changing the gearing 2 teeth at a time this will only yield limited results and require a retune of the clutches so they down shift very quickly to try and save your limited bottom end torque .
The biggest question b4 gear change is to ask yourself where do I operate the machine and what is the max load I encounter .
Good luck with the experimentation

tomo

[jpswift1]

Like I said, before you pull engines or mess with gearing, start by making sure your drive belt is not worn or too lose but not super tight and not worn. That's a very common issue that'll make the machine go slow. Also, check your drive and driven clutches to make sure the parts aren't worn and they're both opening up properly.

[hydromike]

The 950s (and 980s, obviously) I've seen don't allow for the engine to be slid backwards to tighten the belt, so there's a great chance that it could be worn badly enough to cause a big drop in vehicle speed. You can only replace the belt with a new one. The top of the belt should have about 1" to 1.5" of vertical deflection on it (in the center, between the clutches) when you press down with it on your thumb with a couple pounds of pressure. The belt should ride at or slightly above the top of the sheeves on the driven clutch. I think it's a 1-3/16" wide belt on the 950s, if I'm not mistaken. If the belt looks good to you, put the transmission in neutral, open the engine cover and rev the engine up to see that the belt rides to the top of the sheeves on the drive clutch, and that the secondary clutch is opening and closing properly. It's not all that uncommon for parts to break or become worn in the primary clutch, either. I've had a bad habit of neglecting clutches in the past, and they're pieces that need regular cleaning and maintenance to operate efficiently. I think you should be getting way more speed out of a 950 with a 14hp Vanguard. My 980 with 44 tooth primaries and a reasonably tired flat 18 Briggs would almost do 20mph.

[Byrd]

I'm gonna start with the belt this weekend(does seem loose)and look into the 16hp trick with carb and pulling out the restrictions in exhaust.:-) I use my 6x6 as a paintball tank,has a full cage with netting to stop paintballs.I don't need a lot of power ,just enough to keep a slow pace.the reffs keep tanks to a walking speed as not to possibly run a player over and players gotta keep a 10 foot distance from them.where I go to play I just want a little faster travel speed to get me in and off the field as needed.:-) I'll post some pictures of her this weekend as well.:-)

[jpswift1]

Cool. Let us know how it works out. If the belt is loose as you say, that's most likely the issue.......it's quite common actually.

[Byrd]

Here's a picture or 2 of when I was building the cage and before I installed newer engine.:-)

[Byrd]

OK I can easily push the drive belt down 4 maybe 5 inches with 1 finger,heck I can wrap my hand around the top and bottom of the belt to almost touching each other.the belt seems to have lot of slack.I'll post up a picture in a few min.OK heres a few pictures.


Let me know what you guys think.thanks

[hydromike]

Yikes... without even looking at the picture, you need to replace the belt. Since you've put a different engine in your 950, we really don't have a known belt that is going to work with your custom application. You can get close by estimating the clutch-to-clutch center distance, but even then, a quarter of an inch difference in belt length will make quite a difference when you don't have an engine slide to adjust tension. Just in case it doesn't show up in the pictures, what belt are you running now?

Also, can we get an idea of how many teeth are on your primary sprockets? They're the first sprockets that are driven by the transmission on the center axle. I'm just wondering if they're something different than the stock 950 sprockets. I'm willing to bet that fixing the belt is going to go great lengths into solving your 8-12mph dilemma.


::EDIT:: Well, I'll say this much. It's a GREAT way of limiting the vehicle's speed for younger drivers that are just learning! Yeah Byrd, you need a different, shorter belt. It *almost* looks like the belt is too narrow, too. That could also be excessive wear, too. You'll want a 1-3/16" wide belt for those clutches. If the belt number isn't visible on the outside of the belt, can you use a fabric tape measure (or piece of string) to accurately measure the belt you have now? Measure the outer circumference of the belt....

[Byrd]

I'm gonna go to the local Coop and see if they have these type of belts in stock this week,I'll post again once I know something.:-) thanks a lot guys.

[hydromike]

I'm gonna go to the local Coop and see if they have these type of belts in stock this week...

Okay, but just realize you're going to (much more than likely) need a different belt altogether; not just a "new" belt directly replacing that one. If they have a lot of belts and are willing to work with you on fitment, you might want to start with something that's a full 1-3/16" width and at least 1/2" shorter. Some retailers are good to deal with and understand that it's a trial and error process; they'll let you return an unused belt if it's the wrong size.

[liflod]

The center to center spacing on my attex is around 14.25 inches and i'm using a 49 inch belt.