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[Adrian]

+1 to the parts books, they often tend to get overlooked in favour of our hosts' more glamorous(?) accessories catalogue.



A.

[Lord-Toady]

This is my Carburetor there are many like it but this one is mine...







Have taken apart the carb and given the big bits a clean in hot water and fairy liquid and scrubbed with an old toothbrush the more delicate parts I will use carb or brake cleaner on and probably give these bits a going over as well with it. Same for the needle and slide. My bike has a 110 main jet and a 25 pilot jet so standard jetting according to our hosts table. I have not removed the needle yet to see how that is set but i will when I clean it, the brass needle jet doesn't look like it comes out easy so will leave it in and just spray cleaner through it.

[Lord-Toady]

I am not sure what to do now, my bike has has the standard jets but the table calls for new jets to match a more free flowing exhaust. I need to order a few more little bits from our hosts mainly some o rings and seals for the carb and am considering a new slide. I am sure my bike is running rich as plugs gets black and sooty and my bike doesnt like the choke at all and wont run with it but since the rubber on the top of the chole plunger was all rotton and split wouldn't that cause the choke to be permanently on slighty causing rich running?



I may buy new slide and the o rings i dont have and put it back together with the same jets and see how it runs before changing the jets. If I get the better slide hitchcocks sell I dont know whether to get the larger one to compensate for wear or the slightly richer one. I don't want to make my bike run richer than it needs to be and waste money but then it might be running lean after i put carb back together with new seals especially the choke rubber.

[Adrian]

That slide is still perfectly usable from a wear point of view, the only reason for changing it would be for a richer or leaner one to tweak the mixture settings at low rpm.



The choke is actually not a good description, the Mikarb is a copy of the Japanese Mikuni, and the cold start mechanism on these is an enrichener. Instead of a slide or butterfly choke valve to restrict the airflow, there is an extra fuel jet in the carburettor body. On top of this there is the plunger operated by the cold start lever on the side of the carburettor (or cable from the handlebars) The plunger is raised to uncover the jet for starting from cold and lowered to block off the jet one the engine is running. The rubber thingy which has perished on yours is really more of a dust and general crap cover. The only way the cold start mechanism will cause your bike to run too rich during normal riding is if the plunger isn't seating on the jet properly and letting extra fuel through (something to watch out for if you swap to cable control).



The standard jetting on later pre-EFI Bullets was deliberately lean in order to get them through the emissions regulations in force at the time. Our hosts' own silencers tend to be straight-through (i.e. quite loud) and these would needed richer jetting than your new exhaust requires, even though the factory settings for your carb are still a bit lean for what you now have. I think our hosts' little chart allows for the "in-between" jetting options which is where you will probably find the best compromise once everything else is sorted. Have a chat with them when you place your order.



A.

[Lord-Toady]

Thanks I have ordered my o rings and seals for the carb a 117.5 main jet and a 27.5 pilot jet but have not ordered a new needle jet. I have got a new choke plunger and spring as well to hopefully rule out it leaking will leave the slide alone.

[Mark M]

Just remember to fit one component at a time then do a proper test.... (otherwise you won't know what worked. Or didn't!)

REgards, Mark

[Lord-Toady]

Is it a good idea to use the same black high temperature RTV I used on the exhaust on the intake manifold gasket or is that ok as is?

[Lord-Toady]

I have an odd anomaly now the intake manifold studs are too big from the manifold so needs something to pack behind the nuts to let them tighten the manifold, the manifold I have came with a few spare parts with the bike when I bought it and looks just the same as the mikuni type one our hosts sell. I also have another metal one with a lever on it that came with the bike. I am sure I read the lever is is make it leaner in very hot indian climate.

[Lord-Toady]

Well this is frustrating I have the carb back together with the new jets and have raised the needle one notch but the spare manifold I had is not right and the carb will only push into it about 6mm. This means the top of the throttle cable fouls on the tank and I have split the outer braid of the new throttle cable messing trying to get the carb in place. I tried the funny part metal original manifold that came with the bike and the engine runs with it but it leaks so will have to order a proper one from our hosts.

[Lord-Toady]

Well I put the new better manifold rubber on from our hosts it is a great fit. I started the bike up to adjust the idle but it is running so rich now it is smoking.



Maybe I need to go back to the original jets or lower the needle? What should I adjust first?