850 w/Mikunis running problem

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hi splatt,good points but above 1 quarter throttle the needle and needle jets are influenced by the main jets thats why they need to be sorted first, there is of course a certain amount of overlap in each throttle position
 
Re:

Ron L said:
I just bought (on e-bay) a small ultrasonic cleaner, it also heats up the solution. I have tried it on a couple of items with water and soap ( I use Hertel available locally which by itself cleans grease very well) and the parts came out very clean and free of any grease. Aluminum parts come out shiny too. Can't wait to try it on a gunked up carb.
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Perfect, Jean! I bought one like that to clean my scuba regulators when I service them. I have since used it for a couple sets of Amals. A little dish soap (or Simple Green) takes an amazing amount of crap out of the carbs.
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I still really want to try this but, if yo can believe it, I can't find simple green here in a city of 200,000+. I can find simple grren glass cleaner and pressure washer concentrate for sidinge ect. but the regular jugs of simple green are elusive. Sometimes I hate the city I live in when it comes to the simple things.
 
Splatt, I think that is why so many people don't care for the Mikuni's, You can get them set for one throttle position and then another suffers. You are dead right when you mention the vast array or jets and needles you could use. Chris you are also right as they do over lap thru the range. This is why the best way is with a dyno with a good sniffer, Even then you could get lost with changes. But when set up right they are GREAT carbs, Just my opinion of course. Starting out rich is better than starting out too lean I think. Try to think of it as a challenge as not to drive yourself crazy. Ride safe, Chuck.
 
If no Simple Green or other cleaner is available, lemon juice mixed in the water helps out too.
 
chris plant said:
but above 1 quarter throttle the needle and needle jets are influenced by the main jets

really the overlap isn't going to start untill about 1/2 throttle is it???, unless the main jet was so small it was restricting the needle jet
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hi splatt,all i said was that the needle jets and needle are influenced by the main jets,try blocking off the main jets and see how she runs above one quarter throttle, if you,re serious about setting the carbs up start with the main jets
 
Yes, by blocking off the main jet you really do influence the needle jet dont you :idea:
 
Not too veer too far off topic, but has anybody ever had a problem with their oil filler caps leaking?

After changing the oil this weekend (never had a problem before), I went for a 20-mile ride and covered the right side of the bike, and the tire, in engine oil leaking from the tank. Looks like it was coming from the filler cap, so I tightened that down, cleaned up the bike and kept riding. It still seems to leak. I now notice that there appear to be two positions of varying tightness for the filler cap.

Anybody had a problem with this before? Is it possible to replace the cork seal with something better? Could the oil be coming out from somewhere else? I did remove the enormous banjo bolt to clean the screen, but it does not seem to be coming from there, but from the very top of the tank.

Thanks!
-Keith
 
nomadwarmachine said:
Not too veer too far off topic, but has anybody ever had a problem with their oil filler caps leaking?

After changing the oil this weekend (never had a problem before), I went for a 20-mile ride and covered the right side of the bike, and the tire, in engine oil leaking from the tank. Looks like it was coming from the filler cap, so I tightened that down, cleaned up the bike and kept riding. It still seems to leak. I now notice that there appear to be two positions of varying tightness for the filler cap.

Anybody had a problem with this before? Is it possible to replace the cork seal with something better? Could the oil be coming out from somewhere else? I did remove the enormous banjo bolt to clean the screen, but it does not seem to be coming from there, but from the very top of the tank.

Thanks!
-Keith
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Might be a breather problem.
 
I did not touch the breathers or anything apart from the filler cap & banjo bolt. Could I have overfilled (the oil is between the marks)? It seems to come out at the filler cap, though there is so much of it, I can't be sure. Has anybody ever had a problem with the cap not sealing? I had a perfectly dry bike before this!
 
nomadwarmachine said:
After changing the oil this weekend (never had a problem before),
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Did you change to a different brand of oil?

As it sounds as if your oil could be frothing inside the oil tank?

Are you completely certain the oil tank hasn't developed a crack somewhere?
 
This was the first oil change I've done on the bike and I used Red Line 20W50. No leaks anywhere on the bike apart from the oil tank.

I did push the tank out a little to loosen the banjo nut, but I doubt I cracked it (will double check, to be sure).

I have some serious footpeg vibration on this bike, which I assume is related to the Isolastics (?). It may be causing some frothing in the tank.
 
nomadwarmachine said:
I have some serious footpeg vibration on this bike, which I assume is related to the Isolastics (?). It may be causing some frothing in the tank.
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I doubt the frothing, (if that is what it is as it's just a theory?) would start in the tank, but would happen in the engine and then frothy oil woul be scavenged back to the tank or blown back through the breather tube?

I don't think vibration would cause it?
 
When I've seen this in the past it was because somebody changed the oil after it wet sumped without draining the sump. You check it in the yard and it's fine but out on the road it pours all over the bike after it pumps up the other oil.
 
hi nomad, did you change the oil after warming the bike up , or did you just decide to change the oil before going for a ride,i ask because if you did the latter there could have been quite a bit of oil in the crankcase(from wet sumping)so even though you filled the tank to the correct level , the excess in the crankcases would soon overfill the tank but i would expect it to escape from the oil tank breather but i suppose it will get out wherever it can ,just a thought
 
It takes longer to get from the UK Chris, the electrons have to swim the ocean don't they? I'm not sure I'm clear about how all this works....

The particular example we mentioned could come under the "don't ask me how I know" rules couldn't it? I'm sure I've done this but thankfully all I remember is my little brother finding out.
 
Keith did say the oil level was "between the marks" on the dipstick?

Keith, is the cap dipstick the right length? As many replacements are too short.


If there was sufficient excess oil in the tank to reach the filler, then I would have expected some of that oil to have also been blown out of the tank breather tube?
 
lol cookie, what ocean its just a pond isnt it,it does come under the category of how do i know but i did,nt change the oil i just topped it up before a ride,thankfully no one found out, till now lol
 
just had another thought, going back to swooshdaves thought about a breather problem, could the tank breather be blocked ,leaving the only excape route the filler cap
 
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