Running on 3.

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Foxy400
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Re: Running on 3.

Post by Foxy400 » Sat Feb 12, 2022 3:21 pm

Get those thermals on and get out there!

Foxy400
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Re: Running on 3.

Post by Foxy400 » Sat Jun 18, 2022 11:25 am

A bit of an update. The bike ran fine for a couple of months then started playing up again, sometimes only firing on 2 cylinders and the revs would hang around 3-4000rpm when in neutral. Anyway it's back with Graeme France. I know he's stripped and cleaned the carbs (again!) and replaced at least one coil, plus some of the leads. He said it was running fine earlier this week but had yet to take it for a test run. Haven't heard from him since, hope he hasn't broken it!

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Re: Running on 3.

Post by Foxy400 » Sat Aug 06, 2022 1:51 pm

Thought I'd post an update on this just in case anyone's interested.
I finally got the bike back on 4th July. Had a quick run round the block without bodywork. All seemed fine. Took the bike out a week or so later. 40-50 miles no problems. Excellent I thought :grin:

Out on it again today. Running fine for 25 miles. Fast overtake and as I slowed I felt the exhaust note change, it became more harsh. Tried accelerating but there was a power loss. Fuck and bollox!!! :evil: Wouldn't pull much past 8000rpm. Fortunately it didn't stall at the 100's of red lights that were determined to make things worse and I got home.
I checked the down pipes. The rear 2 were too hot to touch but the front 2 were only warm. Clearly it had dropped the front 2 cylinders.

I re-read GF's previous report. He had switched the front coil for a used OEM (tested) because there was corrosion on the lead pins and fitted new ignition leads for the front 2 plugs. Valve clearances re-checked and all seals fine. Carb bowls cleaned. New plugs as well.

It looks like a repeat of the same problem. I can't afford to keep shipping the bike to GF (who's trying to retire anyway). Has anyone got any useful suggestions?

Foxy400
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Re: Running on 3.

Post by Foxy400 » Sat Aug 06, 2022 3:41 pm

I've thought about replacing the replacement coil for the front 2 cylinders, after all it was a used part and cost £16. The OEM part number is 30510 KT 7023. CMSNL are charging £140 +the rest. Bloody hell! I found motorcycleproducts.co.uk who sell them and claim they are Japanese-made replacements for that part number, £38.89.
Going to check the bike now that it's cooled down.

magg
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Re: Running on 3.

Post by magg » Sun Aug 07, 2022 12:10 am

If you suspect the replacement coil why not spare front and rear coils and test when hot. If fault does not move with coil then the front half of the ignition system is suspect. A pickup may be heat sensitive or worst case the ignition box has a heat sensitive fault.

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Re: Running on 3.

Post by Foxy400 » Tue Aug 09, 2022 8:11 pm

When I get a chance (hopefully tomorrow) I'll whip the bodywork off (again!) and either test the coils with an ammeter or simply swop them over and see what happens. That seems the most obvious next step.
Magg, you say if the fault doesn't move with the change-over of the coil, then the 'front half of the ignition system is suspect'. What does that actually mean? I didn't realise there was a front and back half, other than the 2 coils.
Is the ignition box the same as the CDI unit? The original CDI box was found to be faulty last year and changed for a properly functioning one.
Thanks for your help so far.

magg
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Re: Running on 3.

Post by magg » Wed Aug 10, 2022 3:21 am

Apologies for the error in my post where I meant you could swap, not "spare" the front and rear coils to confirm if a coil issue or an ignition box problem.

VFR/RVFs do not use a CDI system. My comment about front and rear sections of the ignition box refers to the output to the coils. If swapping the coils does not move the fault then the ignition box output to the front coil possibly faulty. It may also be a heat sensitive fault, so the problem may not re-appear immediately.

You should also check the wiring to the front coil. Brown/white wire 12v and continuity from the coil to the ignition box.

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Re: Running on 3.

Post by Foxy400 » Thu Aug 11, 2022 6:23 pm

I guessed you meant swop not spare.
Attempted to remove and test the front coil. The primary circuit connectors came off ok. I unbolted the bracket holding the coil and separated the coil. However there was no way my hand was going to fit between the cylinder head and the top radiator to reach the plug caps. Neither could I separate the HT leads from the coil. The caps holding them to the coil has been done up too tight, in fact there are chew marks in the plastic where someone has used a spanner or wrench of some sort. Because the leads were still attached to the plugs I was wary of twisting them. So that's where I'm at.
To get to the front plug caps I know the top rad needs to be shifted forwards, this is assuming the mounting hasn't seized. I shall investigate tomorrow.

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Re: Running on 3.

Post by cbr400rrn » Thu Aug 11, 2022 9:54 pm

Foxy400 wrote:
Thu Aug 11, 2022 6:23 pm
I guessed you meant swop not spare.
Attempted to remove and test the front coil. The primary circuit connectors came off ok. I unbolted the bracket holding the coil and separated the coil. However there was no way my hand was going to fit between the cylinder head and the top radiator to reach the plug caps. Neither could I separate the HT leads from the coil. The caps holding them to the coil has been done up too tight, in fact there are chew marks in the plastic where someone has used a spanner or wrench of some sort. Because the leads were still attached to the plugs I was wary of twisting them. So that's where I'm at.
Chew marks as in used a pair of grips to tighten them up which have slipped type of chew marks?
Foxy400 wrote:
Thu Aug 11, 2022 6:23 pm
To get to the front plug caps I know the top rad needs to be shifted forwards, this is assuming the mounting hasn't seized. I shall investigate tomorrow.
Foxy have faith, the mounting won’t have seized just be nice to it and the bolt will release its grip.



Just don’t use a pair of grips :whistle:

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Re: Running on 3.

Post by Foxy400 » Sun Aug 14, 2022 2:41 pm

Yup, chew marks as in grips of some sort..or maybe they’re teeth marks, who knows?
It’s too hot in the garage atm to mess with the bike but your optimism has spurred me on. As soon as this summer reverts to the normal British type (ie.cold and wet) l shall get back to it.
Also waiting for a call-back from GF, which should be interesting.


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