RD350LC Bellypan

1980 Yamaha RD350 LC 4L0 Restoration – Part 3

Yamaha RD350LC Flywheel

Project Elsie Episode 3 – I mean how hard can it be?

When it comes to getting the flywheel off it is somewhat harder than I had expected!! I had heard that they can be on rather tight and have experienced this sort of thing on outboard engines so wasn’t that surprised. I didn’t have the correct Yamaha puller so I modified one of my standard 3 leg pullers so that the feet would go through the fairly narrow slots on the 4L0 flywheel. It did not want to come loose. I tightened it as far as I dared but still it would not budge. I tried heat, still no good and I didn’t want to overdo it and risk damaging the stator coils behind. Eventually the puller gave way, leaving the flywheel still firmly fixed in place, a correct puller is on order. It is something like a 27mm x 1 mm left hand thread so there is no other puller will do the trick – it screws in to the center of the flywheel then has an inner bolt that presses against the end of the crank.

Yamaha RD350LC Fibreglass BellypanWe had decided to sort the engine first as there are some unknown costs involved and if we hit a show stopper it could all end up being a waste of time – very unlikely but you never know. However, as I am working on my CBR1100XX at the moment there are times eg while waiting for paint to dry where I have a few minutes on my hands so tackling the odd minor job seems both sensible and reasonable. The first such job was to check the speedo works, It does so that’s another thing ticked off the list. Next Item – remove the rear grab rail and clean the tail piece – might as well do the belly pan at the same time. I removed just under 1Kg of dirt, stones and general detritus – it really was nasty. We are not going any further than cleaning these items, the bike will wear it’s age with pride. Sure we could restore the belly pan, it’s fibre glass so easy enough but that’s not what this resto is about.

I had already started cleaning the belly pan when I realised I had forgotten to take a photo

It cleaned up ok.

RD350LC FlywheelAnyways the puller has arrived now so it”s back to the engine. The tool is very simple to use – you just screw it in to the flywheel then use the supplied bolt to press against the end of the crank and the flywheel just pops off. It sounds so easy, doesn’t it. Well in my case it was anything but – the end of the thread in the flywheel had been damaged and no matter how hard I tried I couldn’t get the tool to start straight. I tried putting a chamfer on the end – that didn’t work, I tried chasing the threads in the flywheel – that didn’t work. In the end I had a brain wave and made a simple tool to keep the puller square while I threaded it on – at last it went on and screwed in all the way to the stop. The bolt had a generous coating of copper grease in an attempt to make life easier – I don’t know if it did or not but that’s the kind of guy I am.

The puller needs a 30mm spanner to hold the body and a 17mm to turn the bolt. I tried with all my might with a standard ratchet but it wouldn’t move. I ended up with a 2 foot long breaker bar and still had to apply heat before the flywheel gave up it’s unholy bond to the tapered shaft – it went with one hell of a crack. I thought I had broken the puller at first but it was all good with the flywheel now only being held in place by magnetic force. It took me over an hour for this “simple” task but I guess as it’s the first major hurdle I can live with it. At least taking the stator coils off was dead easy – 3 10mm bolts, remembering to mark the position to make ignition timing setting easier when that job comes along.

While I was in that area I thought I would check the neutral switch as the light had failed to illuminate when I tested the electrical bits and bobs earlier. The switch is fine so it’s most likely a blown bulb or dirty holder – you know Noddy Holder’s Brother – for those of you of a certain age.

Don’t miss the next exciting episode which will be written as soon as I come out of therapy.

Article sponsored by Wemoto.

Article provided by David Powell of Boston Bike Bits.

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