Hi All,
The chain that goes from the transmission to the front wheel drive assembly of my 1987 4x4 Trail Boss 250 needs to be replaced. But I have a few questions.

• Is part number 3224039 the correct number for this chain?
• How many links are on this chain?
• Is there an aftermarket version of the chain I can purchase?
• If a replacement chain is not available, can I purchase a longer chain and shorten it to the correct number of links?
• I noticed that some chains have the option of an o-ring version versus non o-ring. What's the difference and which on should I get?

Note that this 4x4 is used mainly as a utility vehicle and driven on trails versus mud runs or racing. So I do not need some high end type of chain. Just something functional.

Thanks

 

You need to know the pitch of the chain, and buying some in bulk is the lowest cost option. If it is
missing, then measure the pitch of one of the other 2 chains on your quad. If you get one with more
links than you need, you cut it down and put in a master link. Check out some Utube videos if you
want to see it done.

You certainly do NOT need to buy chain from Polaris.

O-ring chain is better, but you do not need it. They last longer.

 

I only had one chain-drive ATV and not for that long so I'm no expert, but I think the O-rings are to keep water, dirt, etc. from getting inside the chain and wearing it out and to keep oil in. There are lots of good chains out there and I wouldn't buy an expensive one from Polaris that someone else made.

 

Yeah, the O-ring chain lasts longer cuz dirt stays out of the link pivots longer than conventional roller chain. New m/cs come
with O-ring chain, but lots of us buy cheaper chain when the OEM wears out, and we lube often. My Kawasaki used massive
630 O-ring chain.

The old 2-stroke Polaris 4x4s are very unusual: they have chain drive for front and rear axles, plus chain drive between engine
and transmission. I have one here with ruined engine, and I fantasize about converting it to electric since connecting the motor
to the trannie would be very easy.

 

With an electric motor you wouldn't need a tranny. The motor speed would control the vehicle speed and you could reverse polarity to back up.

 

The transmission/transfer case allows you to distribute power to front and rear for 4x4. Having a geared reverse also allows for a simpler speed controller. You
can get motor plus speed controller from China that are very reasonable. Designed for scooters (no reverser).

 

Hey guys,
I truly appreciate your responses because they helped me know what questions to search in google and youtube. I had no idea how chains were classified, how they were measured, and what was the difference between chain types.

It looks like my trail boss uses 520 chain with o-rings. I am going to remove all my chains and count the links. My assumption is the main drive chain has the most links but want to confirm. Then I will purchase a non polaris drive chain and shorten it as needed.

Thanks

P.s. the electric atv discussion is fascinating.

 

For an electric conversion I was thinking that you could use whatever transfer case is already on it and wouldn't need a tranny. Electric motors have so much torque you wouldn't need a low range either. As long as the gear ratio from the motor to the transfer case was right you could go anywhere from a crawl to full speed without shifting. A rocker switch could give you forward and reverse as easily as switching a winch to spool in and out. I don't see how adding gears to it would make anything simpler. An electric ATV would be useless to me but it would be interesting to convert one from gas to electric.

 

The transfer case IS the transmission on these old Polaris ATVs. Separate from the engine.

 

I thought the transmission was a CVT. Am I wrong?