Ms460 carb help.

Sloppyslopster

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Hi guys,

Short and sweet just wondering how you guys would go about hooking a 21mm carb to an ms460 jug. I can’t seem to find an adapter for radiator hoses like most carbs do but I know they exist somewhere. Any help is appreciated.
 
Hi guys,

Short and sweet just wondering how you guys would go about hooking a 21mm carb to an ms460 jug. I can’t seem to find an adapter for radiator hoses like most carbs do but I know they exist somewhere. Any help is appreciated.
Get a pumper carb from a saw. You can cut a heat spacer from a nylon cutting board.
 
Get a pumper carb from a saw. You can cut a heat spacer from a nylon cutting board.
Hey again. Thanks for the suggestion I’ll look into soon but for now I went out and got some rubber hosing and hooked it up like that. Now my saw build friggin rips! Also replaced my spark plug so the thing idles now. Actually terrified of this bike now
 

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Hey again. Thanks for the suggestion I’ll look into soon but for now I went out and got some rubber hosing and hooked it up like that. Now my saw build friggin rips! Also replaced my spark plug so the thing idles now. Actually terrified of this bike now
But I’ve ran into a bit of a weird problem. Now I’m not too sure what the max rpm on a ms460 build should be or if it’s my tachometer or something else but the thing only revs to 7000 rpm and it sounds like my WOT and mid range sound the same. I didn’t notice after a good 1-2 mile ride that it was leaking through the base gaskets so the main jet might be jetting aired out a bit. My understanding is that these saw are capable of anywhere from 10-13k rpm? Doesn’t sound like it is revving that high. But overall it’s running great through not many complaints just some tweaks need to be worked out. Especially my idling but that’s gotten way better.
 
It should have almost double rpm. 7k is pretty low for a saw build. Run WOT and kill the ignition while running WOT and see what ur burn looks like.
 
It should have almost double rpm. 7k is pretty low for a saw build. Run WOT and kill the ignition while running WOT and see what ur burn looks like.
I'm pretty sure it's running a little rich, but ill have to wait till the weekend unfortunately because school, but spring break starts Friday for me so ill have all week to finish it. Another detail I noticed that I was having an issue with on my ld100 is the spark plug hole leaking. I might have not bolted it down enough. But ill definitely let you guys know when I can. Can't imagine what 14k rpm is gonna be like. I ran my current stats in a calculator and it was right on with what I ran today (36-38 mph). If it stays accurate I could potentially hit 70 on the bike.

Also quick side note I'm planning on making a full guide on how I built my 460 hybrid. I didn't do the traditional way of jb welding the transfers and re-drilling new holes. Obviously my method is a bit of a WIP, but I think I might have found an easier way to make these hybrids, again just need to work out the kinks.
 
Going off pure memory here, so May need to verify the dimensions, but the O.D. of the intake port on the cylinder is 30-31mm. A PWK 21 is 35mm O.D. where it would meet an intake boot.

Likely the best option you are going to find is a Silicone elbow or straight section 1.25" (32mm) to 1.38" (35mm), OR a 1 1/16" (30mm) to 1.38 (35mm).

A straight one that may work for you. It could be trimmed down some from it's 3 inch length too.
https://www.amazon.com/Straight-Thi...mm+silicone+tubing&qid=1709547969&sr=8-1&th=1

Another straight one, basically the same dimensions from a different seller.

There are angled elbows out there but they are a lot harder/more expensive to get your hands on.
 
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All of the bigger saws have a no load speed of 12,500, which drops down to 9000 under load. So, don't go thinking you're going to get 14,000 out of it. On a china bottom end, with a well ported and piped cylinder you might get 9,000. A little saw, say a MS170, has a no load speed of 13,500, that's with a proper bottom end that will support that rpm.

You're probably good at 7,000.
 
All of the bigger saws have a no load speed of 12,500, which drops down to 9000 under load. So, don't go thinking you're going to get 14,000 out of it. On a china bottom end, with a well ported and piped cylinder you might get 9,000. A little saw, say a MS170, has a no load speed of 13,500, that's with a proper bottom end that will support that rpm.

You're probably good at 7,000.
Aww man that sucks, oh well though. I don’t think 7k is the exact limit of my engine right now though. Realistically it probably around 8000 maybe 9000 if I’m lucky. I still have to break the thing in fully and fix the leaking. So maybe I’ll pick up a bit of power once it’s worked in.

Also do people sell pipes for these chainsaws? Though the only option was the stock exhaust with the weird barrel plates. Also I could consider some porting on my engine but for right now I’ll keep it stock.
 
Aww man that sucks, oh well though. I don’t think 7k is the exact limit of my engine right now though. Realistically it probably around 8000 maybe 9000 if I’m lucky. I still have to break the thing in fully and fix the leaking. So maybe I’ll pick up a bit of power once it’s worked in.

Also do people sell pipes for these chainsaws? Though the only option was the stock exhaust with the weird barrel plates. Also I could consider some porting on my engine but for right now I’ll keep it stock.
If you invent the flange, then you can custom fit a jog pipe. That sort of pipe might get you 10,000rpm. The bottom end is still the limiting factor in all this, they can only take 8K-ish.
 
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