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Oil pressure issue / motor rebuild
K2-K6:
I've been using a Varta ytx14 bs which is a AGM battery on my cbx750. It's one of the best batterys I've used on a bike with really good turn over speed and starting. The cbx doesn't have a kickstart and also a slipper clutch, so if I have to bumpstart it then have to push it about 30mph in second gear to get it to go! It just always spins and starts with this battery unlike mixed brand stuff I've had before. Some of them haven't even lasted a year.
I'm reluctant to call things rubbish, but most of the batterys I've had before come very close to it but this one is great and about £44 delivered. Don't know how that compares to a moto bat cost wise.
MrDavo:
I'll root around and see if I've missed an earth strap in the parts box, I'm sure we didn't fit one.
I can't see it in the parts book, give us a clue if you know where it is, but I know it's important on the 911, there's a copper braid strap beftween the gearbox and the chassis, and the starter doesn't behave if it's not there, because of the high resistance path between the starter and the battery negative terminal. As I see it, we have the same situation here, I'm guessing it wasn't as important with the exhaust on, it's steel, and bolted to the motor and to the frame at the same time, both metal to metal. Anyway it should be put right, as I say we currently have an earth path back from the starter through a painted motor bolted to a painted frame. Now I think of it, the triangular plate at the front offside mount was missing some paint where the engine bolted to the frame, so I gave it a good coat of satin black.
If I have to I'll order a 911 one, hopefully someone can suggest a cheaper alternative, as any Porsche part is reassuringly expensive (but the highest quality).
Edit just seen Triggers post, not sure where my earth lead goes at the moment. I'd file the paint off the engine mount (that bloody paint causing trouble again) but it's in now.
K2-K6:
You can do a quick and dirty test by putting a jump lead from battery negative terminal straight to the sump plug to give you earth bypass and see if it improves.
Cars, I always fit two separate earth leads to make sure it's got redundancy from running a rally car, if one gets snagged or compromised it'll still start.
MrDavo:
That's a good idea.
The Harley has two earth straps as well, but it is a fully rubber mounted engine, so it wouldn't work without.
Trigger:
--- Quote from: K2-K6 on November 21, 2016, 10:56:20 PM ---You can do a quick and dirty test by putting a jump lead from battery negative terminal straight to the sump plug to give you earth bypass and see if it improves.
Cars, I always fit two separate earth leads to make sure it's got redundancy from running a rally car, if one gets snagged or compromised it'll still start.
--- End quote ---
Why run a earth to the sump plug, when you can earth out the starter motor ;)
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