TRF Forums

hi everyone

my drz decided to spit its rotor bolts out about 3 weeks ago.

I have replaced the generator coils...and new bolts which are now loctited in!!!

I have yet to fire it up but a friend of mine had this exact issue and he cannot get his bike to start .....it does not produce a spark.

my bike was still producing a spark.....in fact it was idling fine on the day it happened but would not rev out.

since I turned it off it never started again...then I discovered the problem.

I am going to attempt to get it running this weekend.

can anyone give me any heads up to other potential problems this could have caused?

I was going to drop the sump and make sure there are no metal parts etc in it....the bolt heads were stuck to the inside of the magneto.

very concerned I will have the same issue as my mate.

regards
Dan

The CDI can get spiked when this happens causing it to fail. My ktm lc4 recently did this, needed new cdi new stator and new flywheel
All caused by the flywheel bolts coming loose(wrong loctite when I replaced sprag clutch 2 years previous) 248 should have been 628

Greetings Dan,

This question has been raised before but I don't think the answer was fed back to us.

OK, so you need to consider testing the circuits, as a general guide;

the stator will probably have two/three wires coming from it, with an ohmmeter check for continuity between each individual wire and the centre fixing, if you get a reading then the stator has probably failed due to a 'short' circuit

there is the ignition trigger, two smaller diameter leads, which can be tested similar to the stator for earth leakage

you can check for resistance readings but I think that you would need to refer to a workshop manual or seek an answer on the internet

the regulator rectifier is one unit but two internal circuits, these you check with a diode tester, each output wire to the three inlet wires should flow in one direction only; if there is flow in both directions then it is faulty and needs replacing

the regulator part can only be tested with the engine running and you should get about 13.5v to 14v output - if lower than 13v the battery will not be charging - over 14v and the battery will 'fry' internally

The CDI unit can fail due to a spike of high voltage but I do not have the details of how to check that unit, probably easier test everything else first and then check by substitution.

Make sure that you fully charge the battery off the bike for 10 hours or so and then check its offload voltage before on load voltage. If you can get access to a new type of charger it will do the test as it charges.

Well hope that helps. If you need more ideas photo your unit and cables and repost.

TTFN

Hugh.

If yours runs now fixed swap the cdi box over to your friends or put his on your if the fault follows the cdi box you have your answer. I think there were 2 types with different plugs but a quick look should reveal if they can be swapped.

Sent from my HS-U971 using Tapatalk

What if his regulator/rectifier is cooked and it spikes your working CDI !

Just to narrow things down.

I have replaced the stator with new...this includes pick up.

The bike is producing a spark. Its wont even attempt to fire up.

I have checked that the timing is correct and all seems fine here.

So I'm looking at a electrical issue I assume. I have ordered a new multimeter as mine decided to stop working. I will also check the valve clearances whilst I have cam cover off.

I have had new spark plug in the cap and held it against head and it does produce a spark but visually id say it looks weak.

Valves may be worn?

Ok,

I assume that the bike was serviceable and running smoothly before the alternator failed

So, now the stator and pickup have been replaced but you think that you have a 'weak' spark.

Then we might reasonably assume that the general wiring and the CDI are functioning, therefore the ignition coil might be failing assuming that the coil ht lead and plug cap are not 'leaking' or resisting the flow of electricity I would next test the coil either by measuring the resistance or by simple substitution

Did you fully charge the battery and did you measure its voltage both on and off load You can not do any on bike electrical tests without a fully charged serviceable battery

Off load - battery on its own, you should be looking towards 13.5v - 14.5volts
On load - battery connected and ignition on 13v - 13.5v
Cranking the engine over by starter 11.5 - 13v

To start an engine you need;

compression - valve clearances checked but how about the rotational speed of the engine on the starter with the spark plug fitted is it turning slowly or at normal cranking speed
spark - although there is a spark with the plug removed from the cylinder head the voltage might not be strong enough to jump the gap under compression I do not know the age or condition of the spark plug but in any case I would fit an alternative NGK Iridium spark plug as they can operate at a lower cranking voltage and are less prone to fouling in my experience
timing of the spark is critical - retarded will not work as the piston will be moving down the bore and so the compression will be reducing - too advanced and the spark will possibly ignite the petrol/air mixture but send the piston back down the bore on the compression stroke thus causing a possible 'backfire'
fuel - petrol and air
is the petrol getting to the carburettor - rough check is by removing the float bowl drain screw, with the control tap 'on' petrol should flow out of the bowl
is the petrol of good quality - replace what is ever in the tank and carburettor with fresh quality petrol
is the carburettor sealed both on its mounting to the engine and to the air filter is the air filter clean
is the 'choke' operating - check the plunger
does the carburettor need removing for a thorough clean

Off you go back to the workshop and check Let us know how you get on

TTFN

Hugh.

I think the problem.may lay with the new generator.

Its not genuine Suzuki....last time the generator failed I replaced it with a product from electrux ....worked fine. This one was £44 cheaper from Germany...but I've checked the resistances in relation to Haynes manual specs.

They are as follows

Pick up coil.... Range 390-600 ohms. Reading is 525...which is in range.

Signal coil range 0.5-0.20 ohms reading is 0.27

Charging coils range... 0.5-1.25..... Readings are as follows

0.20. 0.20 then one at 0.16. Which are all below the min of 0.5ohms

I'm.waiting for.my.new multimeter to arrive and I will double check readings.

If they still read out of specs then I shall contact the company for a refund

Greetings,

Any update on this fault finding exercise

TTFN

Hugh.