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bakeyz426f

Xr650l Heavy Rider Suspension/Performance Mods Setup

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My bike has always gotten about 36 MPG since new.  You don't jet for mileage , you jet for correct fueling.

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35 minutes ago, bakeyz426f said:

Does it hurt anything to be running a bit richer?

Shouldn't hurt anything on the bike.  The environment is a different story. ;)

Mine is on the rich side and my excuse is that it helps protect the higher compression engine, which might run hot if it were lean.  Someday I'm going to switch from a 158 main to a 155 and maybe drop the metering needle one notch too.  Just need an excuse to go to the bother of pulling the carburetor out.

With carbureted motorcycles, if they run well I usually leave them alone and just enjoy them.

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If you're running rich enough that the end of your pipe is sooty ,  like you've been burning coal , you're washing the oil from your cylinder and diluting your oil with gas.  

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If you're running rich enough that the end of your pipe is sooty ,  like you've been burning coal , you're washing the oil from your cylinder and diluting your oil with gas.  

I’m running a 150 main, 25pilot, fuel screw 3 turns out, and needle on the fourth notch down.

What are you running?


Is it ok to have some soot but not like it was burning coal just enough to get your finger dirty after a few rides on the inside of a new muffler?

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If it's still like you showed me before , it's OK.  

I haven’t changed anything since then so my guess is it is in the ball park. I’ll see if it gets a lot of soot built up after a few more hours of riding.

With it being just a bit dirty like I showed you after about 2hrs run time would you say it it’s not too rich we’re it would wash the cylinder?

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No.  It's really hard to describe like this and your oil will always smell like gas too.   

So if the exhaust gets a lot of soot quickly and my oil smells like gas it’s too rich. Is there anything else to look at that would indicate being rich?

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This is how the tm40 is pre jetted from procycle.

IMG_4536.JPG

About the same as mine now other than I have a 25 pilot and moved my needle clip one down.

How much of a change does moving down a clip and raising the needle make? Is a big change or slight change in the jetting with a single position change of the needle?

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One notch is a small change of your mid throttle.  You misunderstood about the oil , it will always smell somewhat like gas anyway.  

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One notch is a small change of your mid throttle.  You misunderstood about the oil , it will always smell somewhat like gas anyway.  

I think I’m pretty close I’ll run it a while before I change anything. I was trying to search what jetting others run with a tm40 on the xr650l not much comes up. There’s a good amount of information for the dr650.

Would the xr650l and dr650 have similar jettings with tm40’s?

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Have you looked at the ''jetting repository'' at Jets R Us ?

Here’s what that says it says xr650 on some not xr650l so I was wondering if they meant xr650l
This is the jetting repository.
IMG_4541.JPG
Is this a list of what has worked for other people?

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My assumption would be that the 650s between the 600 and 650L are Ls , but the one 650 on the other side of the 650Rs has to be an L because it's a 2013. Also , as you see , the 650Rs jetting is similar.

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So looks like some people are a couple sizes down on the main and pilot and one person has 150/25 like I’m running.

I tried tuning my bike before I took the smog crap off. With 145/25 needle in the middle clip (3rd) it had a lot of popping and some real loud ones.

 

When I switched to 150/25 and needle clip down one to the 4th rung and tested it again smog crap still on it quit making real loud pops and bangs but still popped a lot just not as violent.

 

Would that be a good indication ruching it up helped some?

 

 

 

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The real loud pops are lean , little ones can be either way , depending on when it does it.

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The real loud pops are lean , little ones can be either way , depending on when it does it.

It only pops when I shift now with the smog crap off and every now and the letting off the throttle but hardly at all. Not a loud pop either.If

 

I’m rich should I be able to start the bike cold without the choke?

 

 

 

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1 minute ago, bakeyz426f said:

It only pops when I shift now with the smog crap off and every now and the letting off the throttle but hardly at all. Not a loud pop either.If

 

I’m rich should I be able to start the bike cold without the choke?

 

 

 

Mine does the shift pop and letting off the throttle sometimes too. Cold starting without ''choke'' would only mean rich on the pilot circuit , which is both your pilot jet and fuel screw combined.

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Mine does the shift pop and letting off the throttle sometimes too. Cold starting without ''choke'' would only mean rich on the pilot circuit , which is both your pilot jet and fuel screw combined.

I’ve been starting it on full choke with a one twist on the throttle before a crank it over and it fires right up. I’ll test to see if it fires that way with no choke.

Is there any way to test to see if I’m rich on the main jet?

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