Topic: Cold Blooded

[nwest4]

 OK, got the magic starter fixed,  thanx for your input on my previous post, it turned out to be the solenoid,  took it apart and cleaned and tested, all ok now.
Now I have a cold blooded bike on my hands, cranks over fine now but is incredibly hard to start and keep running.  low idle screws out about 2 turns I think.  Have been adjusting them out little by little until I can get bike to start.  This seems to be a lot of turns out to me.  I have run the valve adjustment, set timing and dwell, adjusted cam tension, new plugs, etc.  Once bike is warmed up it will restart great, no crank time at all, but cold start I make sure I have the battery charger nearby.  This is a 78 750K.  Now correct me if I'm wrong, but I was always brought up turn the idle screw out to richen and in to lean, but somewhere on this forum I read that if the idle screws are on the engine side of carb, it is opposite.  I'm confused on what I am actually doing when I adjust the idle screws. 
Oh yeah, I have bench sync'd the carbs also.  It seems when I do get this thing running and warmed up, it spits and sputters when going down the road until about 2500-3000 rpm then comes out of it.  Please forgive me for all the questions, but I'm used to single carb bikes and not real familiar yet with quad setups.  Can't wait to tackle my 82 Magna.  Thanks again.

[flatblack]

This is a 78 750K.  Now correct me if I'm wrong, but I was always brought up turn the idle screw out to richen and in to lean, but somewhere on this forum I read that if the idle screws are on the engine side of carb, it is opposite.  I'm confused on what I am actually doing when I adjust the idle screws.

I have the same bike...

Correct; since the "air" screws are on the engine side, they work in reverse: Turn them out to enrich, in to lean.

You said nothing about your choke; how's it adjusted?  These *are* cold-blooded beasts because they're set up so lean.

On mine, normal cold start is:

-- fuel petcock ON
-- choke FULL
-- "blip" the throttle 2-3 times
-- Start

Fires up every time, idles around 2.5-3K.  Which is too fast for my tastes, cold oil and all.  I often spin the engine with the kill switch off until the oil light goes out.

With a combination of throttle and choke manipulation, I can get it to idle reasonably well at around 1.5-2K after a minute or two; it take 5-10 minutes of this before it will idle at 1-1.2K, per the book.

You're on the right track -- just make sure the choke is adjusted well and that you use it for cold starts.

fb

[Klark Kent]

how are your plug caps/wires? 30 years old?  cutting the last 2mm off the ends of the wires and getting new caps could improve performance a lot.  like flatback said there is a certain amount of cold bloodedness inherant, but you may also have to go back and clean y our slow jets and more obscure low idle circuit carb passageways to get your idle sorted- and the synch is important, although i still run on my bench synch from last season.  we need to have a carbtune II that we mail from member to member. 

hope some of this was helpful
-KK

[eurban]

As touched upon by Klark you really need to pay some attention to your idle circuit.  The 77/78 carbs have pressed in idle jets that can be removed with a careful twisting/pull motion.  Once out soak them and run a strand of copper wire through them.  The holes are tiny but you should be able to see light thru them.  Shoot carb cleaner through the passages and make sure your fuel mix screw (this is not an air screw on these carbs) is clean and installed properly with a good o-ring on the end.  I can almost promise that your idle jets at least somewhat crudded up.  You should also visually confirm that the accelerator pump is working properly.  With the air cleaner off and the carbs fueled up, whack open the throttle quickly and observe whether or not a stream of fuel is being squirted out of each small brass nozzles located near each choke plate.  You can also check to see what the actual level of fuel is in your carbs.  Drain the fuel from the carbs, connect clear tubing to each brass overflow, hold (or tape) the tubing high up along the carb body.  Open the drain screws and fuel up the carbs.  The level of fuel in the tubing is the level of fuel in the carbs.  It should be just below the bowl  to carb body seam and exactly the same on each carb.  . . . .BTW if the fuel you drain out of your bowls looks contaminated then don't waste your time cleaning your carbs till you seal your tank/and install decent fuel filterl!

[nwest4]

OK, thanks guys, will look closer at these items and see what I find, BTW I did'nt see a choke adjustment listed in the Clymer manual.
I did notice with the air cleaner removed that the butterflys looked like they closed all the way with no air gap.  Maybe this is my issue since when I do try to use choke
it does'nt even sound like it wants to fire, so have been starting with no choke at all.  Since this is warmer weather did'nt really give it too much thought since my Vulcan will start in this weather with no choke.

[medic09]

I concur with fb's description.  About the same for mine.  Takes me an extra minute to warm up (altitude?).