VM30, cl350, The Gazillion thread *video added*

Jramos13

Jramos13

Been Around the Block
well after almost a year of building it, i started my bike for the first time a few weeks ago, today i finally took it for a spin around the block, ill post a vid later on!, anyway it actually felt really good, it starts first kick now with the mikunis! now the issues,

i have 65.5 pistons and a Fat cam, emgo shorty mufflers the bike wont run with the choke off, i have to put the choke in to start it(normal) but even after its warmed if i turned the chokes levers off it will stall, the bike is running extremely rich there was a bit of gas on the plug and inside the carb boot, at one point a flame was coming out of the top pipe and a few starts before there was a bit of white smoke under hard accel, i put the needle in the leanest setting, sync the carbs and adjuster both cables, the air screw only about .75 out here are the other settings:

Main Jet - #150

Pilot Jet - #50

Air Jet - 2.0

Slide - 3.0

Needle Jet - P-O

Needle - 6F4


here a pic of the plugs:

130223_003_zpsa574e861.jpg


130223_002_zpsc7dd39ec.jpg



so any ideas? thanks!
 
Re: VM30, cl350, The Gazillion thread

well your plugs show rich, but if you're running the bike with the choke on, that's to be expected, the fact that the bike won't run without the choke tells you that it's running too lean. your spark plugs don't record the fuel mixture at whatever point you would like to conveniently study, they pretty much pick up whatever the engine's been doing for the last few seconds before it's stopped. so if you took your bike around the block then stopped and turned it off, they're pretty much going to show how the bike is idling. you kinda screwed yourself by changing a zillion things at the same time, and now you have no baseline for tuning, so prepare for some work. generally tuning starts with getting the main mixture right at wide open throttle, then back from there, and probably back to the main afterwards again
 
Re: VM30, cl350, The Gazillion thread

as for the timming im using the pamco ignition,

well i dint change anything at all, i order the prejetted mikunis, sync the idle air screw with the drill bit method, what can i do to run it with the choke open so i can adjust it a bit better?
 
Re: VM30, cl350, The Gazillion thread

you changed the cam, the displacement, the exhaust, the air filters, there's no such thing as pre-jetted either... and what do you mean by syncing the idle air screw? you can sync the throttle plate or slide, the idle air screws are bottomed out and then turned out the same number of turns to get the appropriate idle mixture. it almost sounds like you bolted this thing together expecting a bolt together affair, this isn't a kit car, old bikes need a lot of futzing to get running right, especially when you modify them. as for getting it to run without the choke, try increasing the main jet. there aren't going to be any easy answers, you're going to need to spend some time experimenting with jetting and probably shell out some more cash for a more expansive jet assortment
 
Re: VM30, cl350, The Gazillion thread

yeah you need to increase your jet size, maby try starting with the needle clip in the middle as well. What intakes are you using? if they have sync barbs on them and they arent blocked that will be leaning everything out and causing your "needs choke" issue (i felt pretty foolish with I realised this myself). also double and triple check your timing. try your idle screws at 1-1.5-.2 turns out until it will idle without choke. 2 turns out is pretty lean so yeah, shouldnt have to go that far.
 
Re: VM30, cl350, The Gazillion thread

Roc City Cafe said:
you changed the cam, the displacement, the exhaust, the air filters, there's no such thing as pre-jetted either... and what do you mean by syncing the idle air screw? you can sync the throttle plate or slide, the idle air screws are bottomed out and then turned out the same number of turns to get the appropriate idle mixture. it almost sounds like you bolted this thing together expecting a bolt together affair, this isn't a kit car, old bikes need a lot of futzing to get running right, especially when you modify them. as for getting it to run without the choke, try increasing the main jet. there aren't going to be any easy answers, you're going to need to spend some time experimenting with jetting and probably shell out some more cash for a more expansive jet assortment
Click to expand...

well i built this engine from scratch, were i live there are virtually no old honda's available, i bought all the engine parts from ebay and put it together, so i never had a stock engine to begin with, by syncing i meant the thumb idle air screw i sync them using the drill bit method so they would idle the same, the air mixture screw i bottom it out then about .75 turn back

ProSimex said:
yeah you need to increase your jet size, maby try starting with the needle clip in the middle as well. What intakes are you using? if they have sync barbs on them and they arent blocked that will be leaning everything out and causing your "needs choke" issue (i felt pretty foolish with I realised this myself). also double and triple check your timing. try your idle screws at 1-1.5-.2 turns out until it will idle without choke. 2 turns out is pretty lean so yeah, shouldnt have to go that far.
Click to expand...

for intakes im using UNI pods 2 stage, the one with the red cover, i will try that to see if i finally can run it with the choke open!
 
Re: VM30, cl350, The Gazillion thread

no the manifolds, are they stock? the carb boots. make sure you have no leaks between the carb and the engine
 
Re: VM30, cl350, The Gazillion thread

the manifolds are the ones for the mikuni carbs, just checked them and the are good!
 
Re: VM30, cl350, The Gazillion thread

"fat cam" pre 70 stock honda and not a performance cam???as mentioned there are a lot of variables to contend with... my carb set up is #35 pilot,165 main,open carbs,electronic ignition,65mm pistons and performance exhaust,,,,,idles like a sewing machine when warmed up ,,hope this helps
 
Re: VM30, cl350, The Gazillion thread

yup, its a pre 1970 one it was from a "type 1" engine, i have the complete upper type one and the lower from a 72, i was reading a lot on the honda twins site ill try a lower pilot to see if it helps, i think a 50 one is to high and i might be choking it with all the fuel and set the idle a bit higher so when i open the choke it wont stall, let see how it goes
 
Re: VM30, cl350, The Gazillion thread

well i installed the 20 pilot and now i can start without the choke, some progress at least, but im still to rich, should i try 135 mains? it still burning fuel heavily, the pipes turned black in like a minute, any ideas?

130302_001_zpsd40fc41e.jpg


130302_002_zps0e74cc56.jpg
 
Re: VM30, cl350, The Gazillion thread

well no i installed 35 pilot jets and 135 mains, the timing is spot on, valve adjusted, and im still smoking and my plugs are extremely rich, heres a vid:

http://s640.photobucket.com/albums/uu121/Mindcrime13/?action=view&current=8929E399-A86D-4FB1-8F85-251653976A29-6573-0000033F31C193FF_zps3bbfcbd3.mp4

with the choke on it helps and doesnt smoke that much, i have the air mix screw about 3 turns out, tried it ith about .25 out and it smokes less, the bike goes throught the whole rpm range just fine, but its smoking and very rich i dont know what else to do:

963F73EA-8DF5-4A63-BAB6-3FD5CC345B75-6573-00000341EAA3F0A5_zps12c12208.jpg
 
Sorry to be a drag, but the "pamco" ignition wold still have to be calibrated in some way when installed. with two sides to the electronic ignition i found that timing one side then the next, then back to the first, and finally rechecking the second again is the only true way to win.

As well you should check the shear pin on the fly wheel, if the motor has ever had a tough start, stop or a seize the pin can be partially sheared and that can result in a few degrees very easily. this can happen from a bad backfire as well. Commonly this will result in a motor being needed to be choked to get over the retarded timing. Black plugs.

Just saying there are two things any motor needs to run. Proper spark and proper fuel. you seem to have concentrated on fuel. time to pull the flywheel and start from basic principles.
 
You are right i cheked the pamco and i adjusted it spot on in the lf and f marks, and i installed a new wuddruff key in the rotor, still smoking and running extremly rich
 
So we get back to Fuel and fuel Supply. What is the Spec'd ID on the fuel supply lines. What shape is the diaphragm in the petcock in. What shape is the mesh filter on the inside of the tank in. How old is the fuel and what octane?

All of the above areas if not in good shape and to specification can result in a motor needing to be choked to operate.

Further to all that and back to Timing, have you checked the position of the timing chain? One tooth on the top sprocket can make a huge difference. The bike will appear to be in time, but it is all lie if the timing chain is a tooth off. Is the Chain tensioner installed correctly?

At this point I am just throwing out stuff. Rattling through thoughts in my mind. and past experiences.
 
my currents setting is: mac 2 in 1 exhaust. 65.5 bore tech piston, 1968 Type 1 "Fat" Cam, Pamco ignition, Mike XS coils

mains: 135
Pilot: 35
air jet: 2.0
Neddle jet 159-P0
Neddle 6F5 1 below leanest
3.0 slide
air screw one out

and im still getting some fouling and black smoke im taking in consideration that i live in a really humid/hot island what in mind i might switch to B7es plugs instead of B8es also if i twist the throttle to fast it just dies and currently my RH carb is backfiring

what im thinking of trying:

Main 135
Pilot 20
Needle jet p4
Neddle 6f5
2.5 slide

im open to suggestions, i have a hunch that my main problem is the slide cuatway to big , that pre-jetted kit is no good really
 
I'd try your Idle air screw start at 1 1/4 if it's too rich back it out a half turn, if it's too lean than turn it in a quarter turn.

Then I'd start looking for signs of an oil leak (black sooty plugs can be oil fouled)

Then I'd start looking at needle jet and pilot jet, I'm running a 25 pilot on my CB350.

but I'm still in the tuning process as well so take this all with a grain of salt ;)
 
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