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[Graham43]

Bearing in mind its awful history as mentioned at length many time on this forum I assume the grunging noise then single clunck coming from the starter on my Electra X is the usual sprag clutch problem?

[Leon Novello]

If it looks like this, then yes, it could be.

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[jefrs]

The problem is far from unique to RE. If you look online it appears as if Triumph own this one. Fortunately it is fixable and repair usually better than the original. Before the blur of spanners, do check the battery is tip-top because it has to spin the motor up, to do that it needs (per book) a 3 second press on the starter button, a quick stab of the button does result in a, "click, clunk, crunch" which does the sprag no good at all. It's the motorbike's equivalent of a car's more robust Bendix drive. If the battery is on its way out the starter will stall letting the motor kick back on the sprag. Once the damage is done the damage is done but you need to positively diagnose whether it is the sprag or some other fault before pulling it apart.

[Gaz262]

After reading all the horror stories on this forum about the sprag & it's engine-crunching destructive urges, I thought I'd made the wrong decision buying my Effie!
- After reading further though, I found the best solution in my case, as the kick-start lever has been removed, is to roll the bike forward gently in 2nd gear until the engine rolls over TDC and then clicking into neutral. Then switch ignition on & attempting the electric-starter.
Works every time so far!
The bike fires up almost immediately & counting up, I reckon the button is only depressed for around 2 to 3 seconds anyway before there being no further need for it.
I hope this helps guys!

[Graham43]

Thank you all for these helpful replies. I will check everything else before stripping the primary side which is quiet extensive according to the workshop manual. Also will try Gaz262's idea. I am fortunate that it is not my only bike so I will want to get riding this summer rather than rebuilding the Electra.

[jefrs]

Pushing it over TDC will only help the first revolution. I believe the starter wants to spin the motor to something like 300rpm. Even on the kick start it spins the crank several times. A half-hearted stab on the button will fail to engage the sprag even on my present C5 which doesn't have a problem. Running the starter places a colossal load on the battery, if it is not in good shape its voltage will drop immediately under load and the starter not spin fast enough. A battery may produce the correct 12.6VDC with no load but when asked to provide the necessary current (amps) drop to 8 volts or less if it's not feeling well. When they get like that, charging it won't help.

It may not be the battery but it is easy to check. And cheaper to replace.



Most modern cars have a delay timer on the starter switch which gives a minimum burst so we no longer get the graunching noise from the Bendix. The RE bikes lack this and require a deliberate firm push on the button - press and hold - until the motor spins up and fires properly, then release.



It was recommended to me (on purchase) to free off the clutch with the kick starter (which you don't have) and continue to hold the clutch in when using the electric wellie, otherwise the starter has to turn the gearbox over as well as the motor.

Concerning the kick start, I don't muck about taking it over TDC - I turn the engine over until I feel compression under my boot and then prod it. No real effort and the starter should feel the same way about its job.

Clip a DVM to the battery when trying to start it?

[PeteF]

Pushing it over compression will help for two revolutions (it's a four stroke) By the time the piston hits the first compression it will be moving at a decent lick and the stress on the starter will be much, much less. I don't know about the C5 but the old iron barrel models had very limited engine revolutions on the kick-start. I think this is why Enfields have a reputation as difficult starters.

[jefrs]

I'm thinking more along the lines that if you have to push it over TDC to help the starter motor then the starter motor is lacking urge from the battery. When you drop a big current draw onto a battery that, past its best, has acquired a large internal resistance, the voltage drops a long way and doesn't spin the starter as fast as it should.



The C5 has this auto-decompressor which requires the motor to be spun up to operate correctly. I reckon the C5 kick start is geared higher than older motors to spin the motor rapidly, more than a couple of cycles, maybe five chuffs. I would not like to operate the kick start without the decompressor with this gearing. It does not however require an almighty kick but a graceful prod.

[PeteF]

No jefrs, you ease it over compression to lower the load on what is a rather a feeble sprag (whether the battery is up to snuff or not) The chance of a "backfire" is much less and that's what does for the sprag.
We're talking about an Electra X here (well the original post was) which, unlike the EFI models, doesn't have an auto decompressor.

[jefrs]

I know the ElectraX doesn't have the decompressor, which is why I was careful to put "C5" into the description. However it only has 7.5:1 compression and with the starter/battery in good order should be able to spin that. It is where the starter doesn't get enough urge that the motor can kick back, which is what damages the sprag; likewise a half-hearted prod of the button, the starter has a half-go and gets kicked back and the sooner or later the sprag is damaged; the starter needs to keep its force on the sprag against the motor to prevent that, it has to keep the sprag engaged, if you release the button too soon the sprag releases and the motor can come back on it like a big hammer. If you've ever kicked a goldie, you know you have to 'go through' or it will bite back. The problem is far from unique to RE, it's actually a poor engineering design but everyone has copied it.