2001 Rs Sprint 955i Wont Start

Starting System Symptoms:

Weak battery symptoms:
-- Slow cranking.
-- Stops cranking suddenly on compression stroke with button pressed.
-- Starts when starter button is released at end of cranking.
Repair:
-- Charge/Test/Replace battery.
Failure Modes:
-- Loss of capacity. Appears to charge, voltage good but no reserve for starting.
-- Won't hold a charge.
-- Low voltage/cell failure.
Preventative Maintenance:
-- Check fluid levels regularly
-- Maintain full charge: Regular riding, trickle charger.

Ignition Coil failure symptoms:
-- Hard starting/misfiring during cranking.
-- Rough idle that can't be tuned out with carb adjustments and carb cleaning.
-- Idle misfire clears with new sparkplugs, returns in a few hundred miles
Repair:
-- Replace: Preferably with Nology for higher reliability than stock Gill coils.
Failure Mode:
-- Shorted turns in secondary resulting in weak spark.
Preventative Maintenance:
-- None
Testing:

Pickup Coil failure symptoms:
-- No spark at all
-- Spark quits with engine hot, returns when engine cool.
-- Note: Pickup coil failure is total. There is no random misfire spark loss.
Repair:
-- Replace pickup coil
Failure mode:
-- Thermal intermittant with long (15-30 minute) period.
Preventative Maintenance:
-- None. Get a spare.
Testing:
-- Ohms checks hot and cold.

Worn starter symptoms:
-- Sometimes won't crank until the bike is rocked in gear.
-- Excessively noisy cranking with a grinding sound.
-- Click from under seat but no cranking.
Failure Mode:
-- Brush wear progressing to commutator damage.
-- Bearing failure related to brush wear.
Repair:
-- Rebuild or replace.
Preventative Maintenance:
-- Maintain battery in peak condition.
-- Follow proper starting procedures. Neutral, clutch in.
-- Crank 5-10 seconds at a time max., switch off for twice as long before cranking again.

Worn sprag clutch symptoms:
-- Very loud rattling when cranking
-- Starter spins but engine doesn't turn
Falure Mode:
-- Breakage
Repair:
-- Replace sprag clutch
Preventative Maintenance:
-- Maintain battery in peak condition.
-- Follow proper starting procedures. Neutral, clutch in.

Worn starter solenoid:
-- Click from under seat but no cranking.
-- Won't crank after rocking bike.
-- Starter continues to run after bike starts and won't stop until the battery is disconnected.
Failure mode:
-- Internal contact damage resulting in non-conduction.
-- Internal contact damage resulting in contacts welding shut.
-- Internal damage/wear prevents solenoid core movement.
Preventative Maintenance:
-- None.
Repair:
-- Replace starter solenoid.
Testing:
-- For no cranking, short across solenoid high-power terminals. Normal operation denotes failed solenoid contacts.

 

I don't know the Sprint RS specifically so am going off general knowledge here.

Daft ones first:
- Have you checked the fuse for the fuel pump (There should be one given it'll have it's own feed)?
- Does the fuel pump work? There should be a small noise of the fuel pump priming the system. Basically it pulls some fuel through the system so the engine isn't trying to run on the air in the fuel lines. There will be a way to test the pump using a multimeter, but electrics aren't my thing (I hate electrical gremlins!!) so not sure what the process would be.
- I assume you've checked there are no leaks/splits in the fuel line when doing the filter.
-Could there be a blockage/clogging in the injectors? I'm guessing the fuel pump sensor is reading fuel pressure in the injectors. Tasty petrol isn't going to help much with a blockage, you'd need injector cleaner or replace them outright.

Does it still run even with the error codes? Does it struggle to get started compared to when it's been error free? How does it run when cold & at running temps (i.e. is there a difference)?

If it was me, assuming the fuses are good & no fuel leaks (even a drip has a massive effect!), I'd see about testing the fuel pump, perhaps remove & clean the injectors. I'd also start trolling ebay for working replacements.

 

One of the biggest causes of problems on EFI systems is bad earths/ paths, it causes all sorts of flaky sensor and component behavior, always worth going through earth connections and cleaning periodically as being open to the weather bikes suffer much more than cars.

 

Glad you got it sorted. I imagine the lumpiness is the lack of running and ineffective fuelling it's had to put up with.

At least you've personally gone over what sound like problem areas & addressed any issues, means you can be fairly confident the fuel system is in good nick

 

Hi all sorry to jump on this old thread but its pretty much the same problem as im having.
Hope you can help. Only just bought this bike and having put a new battery on it started and ran fine. Stared 2 or 3 times no problem atall. This evening i go to start it to take it for mot in the morning and it turns over like a dream but wont start. On the dash it says low oil so i put some in.... Nothing.
Its got pretty much a full tank of good fuel and still nothing. Plugged odb reader in and it says
P0463 fuel level sensor circuit high input
Any ideas as im stumped.
Im good with mechanics but new to bikes so anything too tricky i might have to put it in to be done but if its fairly straightforward ill do it myself

Any help would b good
Thanks