Rhino 428 chain, sprockets, and carb mods
 

I installed a 428 chain and sprockets on the Rhino. I did it to lower the gear ratio and run a sealed chain. The rear sprocket is the stock 40 tooth from an ATA250D. Front is a JTF259.13. Chain is a 118 link DID VX 428 sealed chain. A 12 tooth front sprocket is my preference but the chain wouldn't clear the socket head screws holding the retainer because of the oversize chain plates. The chain has a 7600 lb tensile strength rating. A standard 428 chain does work with the 12 tooth sprocket with a bit of modification of the retainer. With some creative grinding on the bash plate I was able to gain about 3/4" of ground clearance.

Couldn't think of a good reason to post a pic because it really doesn't look any different from the stock set up. Final ratio is about 3.08/1.

I also modded the carb by slotting the float bowl screws and removing the pilot screw plug. An extra 1/4 turn open on the pilot screw helped it idle a little better. Stock main jet was a 94 which I replaced with a 98. I tried putting a shim under the jet needle E clip but it was too rich so I removed it. Engine is running excellent now.

Only things left to do is put on the tach/hour meter and 12V and USB outlets which I'll put under the seat. And I'll put on a Vista Cruise throttle lock.

Throttle lock installed. Why a throttle lock on an ATV? Hitting a bump while standing up at low speed often causes me to unintentionally twist the throttle one way or the other. The quad either slows abruptly, threatening to throw me over the bars and run over me, or jerks forward threatening to throw me off the back. Now I can set the throttle where I want and it stays there. Also works great for setting a high idle during warm up.

I was looking at one of those twist throttles. Pretty neat how they work. Other than it almost making you roadkill, how do you like it?

A twist grip just feels natural after a lifetime of riding motorcycles.

My Peterbilt ATV.

http://chinariders.net/picture.php?a...&pictureid=989

Looks good.. Like the Peterbilt stamp in the front.

Do you have a link for the larger main jet? Would help those looking to mod there stock carbs.

Any place that sells Keihin "small round" main jets. The local Honda shop, Jets R Us, most online motorcycle parts shop.

Please keep us posted on the 428 chain and sprocket mod and how it performs. If it handles it just fine, it makes you wonder why they put such a massive 530 chain on these things. Hell, on my old race bike it only ran a 520!

My girlfriend and I did the sprocket and chain mods on our rhinos and wow what a difference in torque. You can feel the added pulling power. Glad I did it.

twist throttle
 

Cabela.s have the twist throttle conversion kit

So the sprocket bolts twisted themselves loose after a few hours of riding. I used loctite but it didn't work apparently. Is there a torque requirement on these bolts?

Chinese torque specs. Tighten until it snaps then back off 1/4 turn.

I believe those are 8 mm flange head bolts so the standard torque would be 19 ft lbs. I didn't use Loctite when I reassembled and haven't had one come loose but the factory appears to use the equivalent of red Loctite.

Here's a pic of the Vista Cruise throttle lock and twist grip throttle.

http://s8.postimg.org/p6gntkdnp/DSCN3453s.jpg

The stock footrests are too high for an old man with long legs so I modified the stock supports to make footrests at the same height as the frame bottom. Had these on the ATA250D thus the gray color. Will paint them black when the weather warms.

There is nothing to keep your heels away from the back tire but my size 13 feet hang over the front and get nowhere near the back tires. Had to make a support for the rear fender to keep it from flexing without the plastic foot wells. Shifter came with a new Lifan 200 engine for my motorcycle. Brake peddle is modified with stuff from the metal pile.

http://s2.postimg.org/6nf4v1zy1/DSCN3445.jpg

http://s21.postimg.org/czh5ziv6v/DSCN3448.jpg

http://s23.postimg.org/9jvw522zf/DSCN3449s.jpg

http://s30.postimg.org/vsctlnoxt/DSCN3451s.jpg

http://s17.postimg.org/acv65t4jj/DSCN3455s.jpg

One other mod you'll see in one of the pics below is a 1" wire holder holding the bottom of the regulator to the frame. The tab that holds the regulator in the stock setup eventually breaks from vibration and your regulator ends up dangling from the wires.

Great job mud. Bet your feeling satisfied!

One thing I haven't seen mentioned in other Rhino threads is the air filter element needs to be oiled. It comes dry.

I like what you've done with your machine. I just ordered everything to switch to 428 chains and sprockets on our Rhinos. going to 40 tooth rear and 12 front. What size are those Bear Claws? I couldn't find them in 22x10-10. Merry Christmas!

The Bear Claw tires are 23x10-10 which gives it a bit more ground clearance.

Somewhere I made a post about doing away with the front sprocket retainer plate and replacing it with a spacer and a couple circlips. You'll probably need to do that in order to run a 12 tooth.

Thanks! I picked up a retainer from Whynotstock that's supposed to fit the 12 tooth sprocket/428 chain. This weekend we're swapping out the chains and sprockets on both units! I can't wait.

I found that if you grind down the retainer like Whygostock it'll work with some chains that have smaller side plates. Won't work with some chains like the DID Xring chain I use because of it's bigger side plates. Tried it with the Unibear chain that some folks use and it touched the socket head screws but still may work.

Just back from my 2weeks off. I swapped the front and rear sprockets to a 12 tooth and a 40 tooth and went to the 428 chain. The 428 front sprocket is noticeably smaller in diameter than the 530. The rear sprocket at 40 tooth was the same diameter as the stock 32 tooth 530 sprocket. I had to grind the front sprocket retainers down myself.The process went pretty smoothly for both Rhinos. We test drove them in the desert around our ranch and there is a considerable difference in hill climbing ability as expected.
The next day we took them out to Stanton, AZ to try to get to a particularly rough area to check out some gold claims way up in the mountains. It was much too rough for the Rhinos and my chain started jumping on the sprocket....Im over 200lbs. My son is only 130lbs...had no problems. We were more like rock climbing than driving on jeep paths. My chain started jumping more frequently and we turned back. As I started back...I thought I blew my clutch. The gear wouldn't engage but the chain seemed to still be on the sprockets. We hooked up a tow strap and my son towed me back to the campsite. Once there, I pulled the front sprocket cover only to find the chain did indeed jump off the front sprocket and was hung up in thr cover. Mad as Hell cause I could have fixed that in the field....but happy as can be cause no clutch repair was necessary. I cant fault the units. They had no business on that boulder laden path. Engines were flawless and we still love our Rhinos!!

Let us know if you figure out what caused the chain to come off. I'm over 200 lbs and do a lot of boulder bashing also but the chain has never come off. I removed the tensioner on mine because I didn't like the noise it made.

Kinda thinking it isn't lined up right and true.

I had that issue with mine when I did the sprocket change. Didn't realize there was a little bit of a offset on the rear sprocket. Was enough to see the chain wasn't in a straight line when you looked down it like a rifle sight.

I imagine if I tried to ride it like that the chain would pop off.

That tensioner bends really easy...one hit on a rock and it's knocked crooked. I think I will pull it off as well. I'm back in North Dakota for a month and plan on going through everything again. I've been trying to get up to this area for way too long to give up now. I tack welded the front sprocket retainer to it's bolts...that kept really well on both quads. I videoed the sprocket swap. I will edit over next few days and post. Thanks for the support.

Hey Darth
I plan on doing some lining up and retightening of everything related to that axle. Those 4 bolts that secure the axle carrier seem to like backing out when the going gets tough. I will take a hard look at that as well. Hey...troubleshooting is half the fun! You been rerunning cons to get through the winter?

Inspecting things today I noticed the swing arm is cracking in the same place as the one on the ATA250D. Removed it to take to the welding shop. I'll reinforce it when I get home in March.

When you have the rear end jacked up in the air, line your eye right on top of the chain like your aiming a rifle. If the chain is under tension you will see what I mean. There will be a noticeable bend in it left or right.

There is a thread somewhere in this board about using ratchet straps to true the rear axle (rear steer) which might help the situation.

Post about aligning the axle;

http://www.chinariders.net/showthrea...rap#post232279

I was able to align mine pretty well using my Motion Pro chain alignment tool and a strap on both sides. They're less than $15 and work very well with a very simple concept.

https://www.amazon.com/Motion-Pro-CH...alignment+tool