E: Engine Comet Mongrel

Black Flash

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Well Cyborg,
I don't know anything about prices in Canada, but over here prices for mikuni jets are dirt cheap. On fleebay you can get sets of 10 in rising oder for about 20 U. S. They won't be more expensive in your country.
Safe your time and buy a set, it is very extolling to fiddle around and get the best set up carb around.
 

Cyborg

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I did find some kits for mains that were cheap and can't imagine they can screw up something as simple as a main jet.... although I would be inclined to measure them. The cheapest kit I could find for primaries was a kit for $85 USD. The single no name ones from Taiwan are cheap, but I need the VM22/210 style and don't know if I would trust anything other than the OEM Mikuni primaries. They can be had for around $6 each, so still thinking drill the 15 primary I have, figure out what is close and then buy 1/2 dozen in that neighbourhood. I read somewhere that the selection of needles and needle jets for that flat slide are limited, so do hope I don't have to spend any time finishing a needle.
 

eglijim

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I did find some kits for mains that were cheap and can't imagine they can screw up something as simple as a main jet.... although I would be inclined to measure them. The cheapest kit I could find for primaries was a kit for $85 USD. The single no name ones from Taiwan are cheap, but I need the VM22/210 style and don't know if I would trust anything other than the OEM Mikuni primaries. They can be had for around $6 each, so still thinking drill the 15 primary I have, figure out what is close and then buy 1/2 dozen in that neighbourhood. I read somewhere that the selection of needles and needle jets for that flat slide are limited, so do hope I don't have to spend any time finishing a needle.
Purely as a set up exercise do you not have any other carbs from a running bike just to get you off the ground safely before starting with an unknown setup ?. Usually easier and safer to start with a setup on the rich side then work leaner once running.
 

Cyborg

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Welcome back....
I don't really have anything other than a pre monoblock that is good to go. Room is very tight and I have to make a new manifold or an adapter to change the angle of a stock manifold. You are right about starting rich. As mentioned, the plan was to drill out the primary until I reach a point where it's starting to behave and then buy a few jets. Then I started thinking about the chrome on my nice new pipe. Once I get the primary sorted, if it has drivability problems from the needle and main etc, I'll trailer the bike to a safe location for plug chops. It's deadly riding around here at the best of times. On a side note, I do have one of those colour tune setups that my brother bought back in the dark ages, but I've never actually tried it. Think I'd rather stare at a plug instead of peering though an ancient colour tune. Would feel like staring down the barrel of a gun to see if it was loaded.
 

Chris Launders

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Here's a handy tip if you don't want to blue your pipe, a friend used to do this on his HD and it works !!
I used it on all my custom bikes.
Buy some Sperex VHT exhaust paint (this had found worked the best, mind you it was 30 years ago).
Block one end of the pipe with a potato and spray loads of the paint into the exhaust, keep sloshing it about until it's all sticking, leave it to dry, swap ends with the potato and repeat, do this a couple of times until the inside is well coated, it will give you a heat resistant barrier inside the pipe.
The colour tune will give you an indication of the mixture instantly, whereas with the plug reading you will have to run it at a constant speed and load it "colour" the plug.
 

timetraveller

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If your colour tune still has all its original bits then they came with a plastic tube and mirror so that one can look into the mirror and not straight down at the flame. Personally I have no worries about using mine and looking straight down at it.
 

Chris Launders

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I've used them for years, my twins both have the extra plug hole so I put the colourtune's in there, I recently forgot to take them out and rode several miles until it dropped on to one, they had only been in finger tight and one came out, not the inside but the whole colourtune had unscrewed itself.
I've never heard of one losing the inside and they've been around a long long time.
 

BigEd

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VOC Forum Moderator
Welcome back....
I don't really have anything other than a pre monoblock that is good to go. Room is very tight and I have to make a new manifold or an adapter to change the angle of a stock manifold. You are right about starting rich. As mentioned, the plan was to drill out the primary until I reach a point where it's starting to behave and then buy a few jets. Then I started thinking about the chrome on my nice new pipe. Once I get the primary sorted, if it has drivability problems from the needle and main etc, I'll trailer the bike to a safe location for plug chops. It's deadly riding around here at the best of times. On a side note, I do have one of those colour tune setups that my brother bought back in the dark ages, but I've never actually tried it. Think I'd rather stare at a plug instead of peering though an ancient colour tune. Would feel like staring down the barrel of a gun to see if it was loaded.
The plug colour is not necessarily a good indication of mixture these days with various additives and percentages of alcohol in petrol.
I've never heard of a Colourtune exploding and it is probably easier to get an idea of what is happening in the combustion chamber stationery in the workshop than riding up and down a road.
 
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