Why wouldn't your Mastff/Baggy start?

[andyw]

I posted elsewhere about my Mastiff not starting ( http://www.mzriders.com/viewtopic.php?t=1425 ) - looks like some help troubleshooting may be needed

If you've had a non starter please post details of what the problem/solution was here, which'll help me now and no doubt others in the future

Thanks

[keithcross]

In the past I have ahd two ocasions when my Baggi wouldent start. The first was when the batter went dead suddeny, the second was when one of the wire on the pug for the ignition unit broke.
I also had a wire to teh ignition that boke when I was out green laning.
Hope this helps.

Keith

[dmon722000]

Spark, compression, and fuel... Since the motor is bulletproof, we have compression for sure. I worked at a dealer for years and we saw a few hard starters (1 in 10). The sparkplug we changed without hesitation and we also eliminated the evap system (no that isnt a coffee can on the left side of the motor) due to the fact that the fuel signal is delayed by this system for "emissions purposes". The casnister (EVAP) is filled with charcol and was intended to absorb gas in case of a tip over unfortunately absorbs fuel vapor also wich slowly turns the inside of the canister hard (like coal) and air and fuel signal is "pinched off" slowly. Remove the canister for free HP and vastly improved starting manners and throttle responce. We normally have the air screw backed out by 5 1/2 turns from bottom and do not apply any throttle imput during startup w/ choke activated. If the idle is too low with the choke on to start the bike increase the idle using the idle adjustment screw NOT through the twist grip or else Fouled plug... Also the idle jet is a puny one at best, my 50cc scooter has a bigger idel jet, this can leave even the best mechanics scratching their heads. You could pull the carbs (as a set, through the right side of the bike, trust me) in about 2 hours start to finish, giving them a good cleaning by removing the main and idle jets and using a piece of stripped wire and carb cleaner. On a note, I left my bike one year completely unaddended and uncovered and untouched. Went out before a hurricane landed on us and she fired up like it was used an hour before. Hope I shed some light....

[keithcross]

All good advice from dmon, with one exception, UK models dont have the evap system fitted

Keith

[dmon722000]

Attack the plug and idel jet I suppose and dont forget to blow out all of the air/fuel passeges with some good ol' carb spray (also remove the choke assembly via a 12mm wrench)to clean the choke passeges for good mesure... Drain the fuel tank completly cause any water caused by condensation in the gas. Those black plastic tanks absorb heat and cold like a ill made thermos.

[DAVID THOMPSON]

do not apply any throttle input during startup w/ choke activated.

i have found that this applys to most bikes made in the last 15 years
my rt125 just flat refuses to start if you open the throttle any
till its running
dave

[dmon722000]

Have you tried starting spray (ether), It both smells great and starts stuborn machines, makes a great degreaser too!

[DAVID THOMPSON]

starter fluid can cause a rt125 to be dead for weeks
probely the worst thing to do to a 125 when its being cranky

fuel to air mix on bottom of carb at 2 turns out seems to make it happy

[andyw]

Great stuff so far guys, appreciate the tips and advice

I think I'm looking at a two sided problem........for one the spark is weak (will work through all electrical connections, clean and reconnect etc) but I think there's a carb problem also, possibly flooding - so the carb will come off for a clean up as suggested.
Anyone tell me what's the best settings for all jets please (and which one is which )

Thanks........keep the tips coming

[andyw]

Found a few not so good electrical connections but nothing that I'd have thought would stop the bike starting/running........still more to do though!

Got the carbs off now and could do with some more advice......

Carb cleaning / check-over

Thanks again

[phlat65]

weak spark is hard to tell with out proper testing equipment. low voltage output on the secondary side of the coil can be caused by multiple things, low voltage on the primary side, the igniter not pulling the primary field down close enough to ground, incorrect dwell ( unlikely with electronic ignition) or a shorted secondary winding.

at the coil, you can check the primary resistance between to 2 12 volt terminals, and the secondary resistance from the coil tower and one of the primary connections. check the resistance of the plug wire also, high resistance will cause the coil to disipate its energy elsewhere. make sure you have close to battery voltage at the coil while cranking.

without testing my good coil, I would guess the resistances should be between 1-3 ohms on the primary side, and somewhere around 20k ohm on the secondary side. the plug wire should ba about 1k ohm per foot.

good luck!

[andyw]

Thanks for the further input/suggestions

The saga continues

Still working through every electrical connection I can find, disconnecting and cleaning before reassembly and a good squirt of AFC50 to keep moisture out. Checked the ignition coil (primary and secondary circuit resistance), the HT lead and HT cap - all ok.

Started a new thread on electrics as, surprise surprise, I need some more help!

http://www.mzriders.com/viewtopic.php?t=1442

Thanks.........as and when I meet you guys it's going to cost me a fortune in beers LOL

[DAVID THOMPSON]

when I meet you guys it's going to cost me a fortune in beers LOL

that's why we all live so far apart
one should not drink because it cuts into rideing time