[mythos]

99 500cc with boyer brandsen mk4 KS (converted from ES)
New battery.
Cam timings properly set. Rockers and pushrods in good condition. Valves in working condition.
Compression check. Spark check.
Carbuerttor cleaned/rebuilt all parts there.
Coil resistance check. Contacts and grounds are good.

I cant seem to figure out why my bike wont start. It backfires into the carb every time I try to kick it over. Could this be an issue of low voltage going to the ignition? My battery voltage is at 12.76 but if i charge it can hold around 13. It's brand new.

[rep_movsd]

Is the alignment of the unit correct? Perhaps it thinks TDC is earlier than it really is?

Do you use the choke when starting? If not it may be a tad lean. Also check for air leaks on the intake manifold rubber

[High On Octane]

Spitting back thru the carb is either going to be timing is too retarded or the carb is too rich.  If there is any kind of mist of fuel spitting out the carb then it is going to be too rich of a carb tuning.  If it is just spitting then the ignition is likely firing too soon.

[mythos]

the position of the unit hasn't been changed ever. i forgot to write that i checked the intake manifold and its intact and has no leaks. i also remembered the gas is about 4 years old and the plug was not properly gapped, going to try again when this rain lets out

[Mr.Mazza]

the position of the unit hasn't been changed ever. i forgot to write that i checked the intake manifold and its intact and has no leaks. i also remembered the gas is about 4 years old and the plug was not properly gapped, going to try again when this rain lets out

4 year old fuel will do that! Try a fresh, gapped plug and fresh fuel and see what happens.

[mythos]

So I flushed the tank and cleaned the carb thoroughly and still more of the same! The spark plug has been gapped as well.

It just makes a loud high pitch pop and doesn't start. I am beginning to think it's electrical however there is one detail I omitted from my original post. My oil pump is shot, 3 of the teeth have been ground up pretty bad. Worm nut is intact still. Could this cause a backfire?

I changed from a clubman exhaust to a goldstar(no baffle) but it ran fine for quite some time before it was put away and I was told no rejetting would be necessary is this true?

I also changed from an acid/lead battery to a smaller sealed gel battery. Could this mess with the timing on the MK4?

Thanks

EDIT: I also noticed my spark is a bright white. Isn't it supposed to be blue?

[ace.cafe]

DO NOT START THE BIKE!!!!!

If you run the bike with a dead oil pump drive, the engine will be ruined very quickly.
The broken spindle teeth are the result of kickbacks, not the cause of them.
You must fix the oil pump system before going any further.

If you had the timing cover off, and if you had the cams out, or any of the idler gears off, and the engine was moved off TDC at all during the process, then the igntion timing may be off, and even the cam timing might be off.

What did you have off when you had the timing cover off?

[mythos]

Hey ace thanks again for replying.

I know for certain I removed the cams, I'm not sure about the other gears inside the chest. How would I go about recalibrating them (assuming they have all been fiddled with).

[ace.cafe]

Don't turn the engine from where it is now, until we get to the point when I ask you to turn the engine. Hopefully, you haven't already bent the valves. If you haven't, then we don't want to do it now.

Take off the timing cover .
Tell me when you have it off, and we will then go to the next step.

[mythos]

timing cover is off

[mythos]

AFAIK the piston is at TDC. I'm not the original owner and I didn't install the MK4 so I'm not 100% sure on which marking is the correct one.

[ace.cafe]

Remove the cams.

Then turn the engine until you reach TDC. The crankshaft pinion gear should have the dot visible at around 1:30 o'clock position.put the exhaust cam on, so that the 2-dot mark aligns with the dot on the crankshaft pinion gear. Then, put the intake cam on, so that the single dot on the intake cam aligns right beside the single dot on the exhaust cam. The cams are now installed correctly.

Do that, and tell me it's done, and then I'll tell you how to set up the ignition timing in synchronization.

[mythos]

aye aye captain!

[ace.cafe]

Okay, now leave all that stuff right there, and don't turn the engine anymore now.

Now, take the distributor cover off, and have a look at your Boyer Mk4 ignition.
See if the unit is lined up with the magnet at the trigger coil, just like they tell you to set it up when you install it new.
If it looks like that, then go ahead and do the check that they tell you to be sure that it is timed right.
If it doesn't look like that, then let me know, and I'll let you know what to do.

[mythos]

looks right ace