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Rich or Lean?

versuspop
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Posts: 205
Joined: Thu May 07, 2009 9:06 am
Location: columbus, ohio

Post by versuspop » Wed May 19, 2010 7:14 am

They have those clips at Lowes Hardware--if you have that out in CA.
I'm not saying they have the right size, but last time I was there I saw a drawer with those clips in it.

I would try to get everything back to stock and start from there. LM knows what's what and I would get the jets that are the size he recommended and set the clip at the 2nd as well....

Further, yes- even the smallest little bit o' crap clogging any of the jets can cause serious problems with throttle response and idle.

Once you have everything in front of you, pulling the carbs and doing a thorough cleaning only takes a few hours (if you need to soak anything). You should be able to ride the same day or the next.
MBellRacing wrote:So the main jets are 145's but the needle is in the bottom location. I think I'll keep these jets (since it was lean to begin with) and just raise the needle... wise?

I broke one of the little clips that adjust the needle height-- I'm using a ridiculous tool for the job and it proved to be a bad choice... does anybody know where I can get another one of these? I'd prefer to go pick one up than order one.

eyhonda
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Location: The Motor City
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Post by eyhonda » Wed May 19, 2010 8:06 am

As far as telling if its rich or lean, you can kinda sorta tell from the sound of the intake and the throttle response. This takes a bit of experience. Ride it with a half helmet. If it is rich, it will sound "wet/slurpy" and the throttle will feel boggy with a delay. If it is lean, it will sound "dry/tinny" almost like a 2 stroke and the throttle will feel very crisp and might miss. Due to your larger jets and the description of your throttle response, it is rich.
63 cb77 cafe
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MBellRacing
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Posts: 178
Joined: Sat May 15, 2010 2:23 pm
Location: San Mateo, Ca

Post by MBellRacing » Thu May 20, 2010 12:56 am

So I've been busy...

I pulled the plugs and found that only one was consistently firing. The one that wasn't firing was MASSIVELY lean. My neighbor was luckily disassembling a Superhawk and let me take his right side ignition from him. I put it on, and LIKE A MIRACLE, it fired up and ran like a champ!!! I fixed the timing but now found that it was having some missing still in the last bit of the throttle range. I steadily increased jet size and it progressively got better and better. Now I can go full throttle and it revs quite high in 1st and seconds gear. In higher gears (higher load) it still struggles a bit and sounds lean still. The issue is that I am now on a 145 main jet with the needle in the middle slot. This sounds quite rich but its working just fine in both cylinders. I know there is a slight overbore in this engine but I feel like it is getting out of hand. Is something wrong? Could something like an air leak or something be causing me to need such fat jets?

Edit:
So I went out and pulled the plugs again. Where before the ignition change the right side plug was completely washed and clean, now the left side looks okay and the right is BLACK. Could this just be from all the old fuel that had likely filled the cylinder? Or is something else going on? What can cause this? Could a dirty filter be the culprit?

Image

versuspop
honda305.com Member
Posts: 205
Joined: Thu May 07, 2009 9:06 am
Location: columbus, ohio

Post by versuspop » Thu May 20, 2010 8:20 am

It's hard to say. You need a more sceintific approach to the whole thing. The goal is working toward isolation of a particular issue. Also having a control or baseline from which you are starting will help everyone here help you.

It seems to me, though I am no expert, that you have communicated a few potential issues. ( jets clogged--there is more than the main hole rinning through the jets. there are holes in the sides of the jets, as well as vacuum jets in the carb body itself-- or jet too big, needle depth, float height measurement etc.

Start from the begining.
Proper jet sizes, needle depth, float height, carb sync, clean body jets, springs in carb adjustment screws, clean air filter, flat carb insulator, good o-rings, timing, valve clearances, fresh plugs. good spark, compression test.
Then- follow ed's tune up, to the "t".

Hope this is helpful. I have found myself in the same situation many times --always kick myself for not starting from the start...
MBellRacing wrote:So I've been busy...

I pulled the plugs and found that only one was consistently firing. The one that wasn't firing was MASSIVELY lean. My neighbor was luckily disassembling a Superhawk and let me take his right side ignition from him. I put it on, and LIKE A MIRACLE, it fired up and ran like a champ!!! I fixed the timing but now found that it was having some missing still in the last bit of the throttle range. I steadily increased jet size and it progressively got better and better. Now I can go full throttle and it revs quite high in 1st and seconds gear. In higher gears (higher load) it still struggles a bit and sounds lean still. The issue is that I am now on a 145 main jet with the needle in the middle slot. This sounds quite rich but its working just fine in both cylinders. I know there is a slight overbore in this engine but I feel like it is getting out of hand. Is something wrong? Could something like an air leak or something be causing me to need such fat jets?

Edit:
So I went out and pulled the plugs again. Where before the ignition change the right side plug was completely washed and clean, now the left side looks okay and the right is BLACK. Could this just be from all the old fuel that had likely filled the cylinder? Or is something else going on? What can cause this? Could a dirty filter be the culprit?

Image

MBellRacing
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Posts: 178
Joined: Sat May 15, 2010 2:23 pm
Location: San Mateo, Ca

Post by MBellRacing » Sat May 22, 2010 1:27 am

So I think I've finally figured it out! I had the same pilot jet get clogged TWICE now. A little piece of rust from the top of my tank (most likely) found its way in there-- again. I noticed that the blackened spray was heavier on one side of the plug and thought that it likely either meant I had a leak in the cylinder (either through the rings or through the valves) or I had bad atomization. I checked compression and it was the same in both cylinders. Since I knew only one was experiencing a problem, I figured that it was fine. I pulled apart the carb (for the 1000th time) and once again saw that the pilot was clogged but the main was fine. It's a just a touch rich now in both cylinders, but I figure that's better than lean! It seems richest on transitions from very low to mid-range throttle. I think I'll lower the needle considering I've moved to such a big jet. I think this engine has a MASSIVE piston in it, just as the previous owner said it does. Anyway, thanks for the help, you are all are a great bunch!

teazer
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Joined: Mon Feb 08, 2010 10:32 pm
Location: Midwest US

Post by teazer » Sat May 22, 2010 10:09 am

Good to hear that you have found the problem. Now that is fixed, I think you mentioned that it's still rich. That could be the main or the slow jet or both.

I'd go back through the process to get the right main jet (probably 140) and the correct slow jet and then fine tune the air screw and needle position.

Your'e getting close now.

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