RD350LC Restored

1980 Yamaha RD350 LC 4L0 Restoration – Part 12 (Are you starting or what? The conclusion)

I am still waiting for parts, which are on their way but may be delayed a few days because of the lockdown. I moved the bike to the other lift so I could get the wheels off – a new pair of tyres are coming as part of the consignment. I will get them fitted and put the bike back on the floor before fitting the idle mixture screws, which are also coming. I will then be able to attempt a start after what seems like an eternity. It has only actually been just under 4 months as I took delivery back in January. In normal times I think I would have been finished a good while ago and if the engine hadn’t taken so long to fix it would have been even sooner.

RD350LC DID chain and sprocket kit from Wemoto

RD350LC DID chain and sprocket kit from Wemoto

While it was on the smaller lift I did a couple of jobs that had been harder to get to on the other lift – the main one being the rear brake light switch. I had a spare one to put on so that got done. Sadly the end of the spring that goes from the switch plunger to the brake pedal had rusted away so I had to reform the end. Fiddly job when working underneath the bike but it works reliably now so that’s another job ticked off. I noticed there was a slight oil seepage around the right hand gasket. There shouldn’t be as I was really careful to remove all traces of the old gasket from both faces, I have nipped the bolts up a wee bit tighter, if that doesn’t fix it I will have to take it off again to see what is going on. I don’t expect it to be a major problem.

It looks like a case of one step forward and two step backwards but the next time you see it the wheel will be back on and it will look a lot more complete. Now we have a case of perfect timing because as I sit here writing this drivel the postman has just bought me the latest delivery from www.wemoto.com – a DID chain and a pair of mighty fine looking sprockets. The bike desperately needs these, I think they last got changed some time in the 17th century and it looks like the last owner gave it some serious stick  because the teeth are really badly hooked . I’m just glad I don’t have to clean it, it’s proper nasty. I reckon it needed changing a good couple of thousand miles back.

This lovely shiney new stuff from wemoto will do the job perfectly. They do several different chains at a whole range of prices – this is like a mid range one.

RD350LC twin hornsAnother couple of little jobs got done, namely the new throttle cable was installed and a nice shiney new pair of horns were purchased and fitted. The horns are one of the things that differentiate the 250 from the 350 as the 250 only had a single one and the 350 had a low tone one and a high tone one. We had the originals but I couldn’t get them working properly and they were pretty grubby so for the sake of £30 we now have the front looking like it should. I bunged on a pair of better mirrors that came with the bike while I was at it, a nice NOS indicator lens was ceremoniously put in place on the left hand front indicator to complete the look of splendidnous.

The throttle cable was one of those jobs that took a lot longer than it should have done, partly because I didn’t understand the way the cables fitted to the carburettor slides. There appeared to be two small cross head screws holding it all together but in actual fact these do not need to be removed. There is a metal clip that has to come out to allow the cable to be removed but when you know how it’s quite easy to do. I had already removed the 2 screws before I spotted that they were not actually holding the retainer in place. Sorry I forgot to do a photo and there’s no way I am taking it all apart again – you need minute fingers and a lot of patience.

The cable splits in 3 – one end for each carb and the third one for the oil pump which varies the amount of oil delivered as the throttle gets opened. You have to synchronise all three so that the carbs are balanced and the oil pump is delivering the right amount of oil for any given throttle setting.

The carbs are synced by aligning dimples in the slides with little viewing windows on the sides of the carb bodies – when both dimples are central in the windows at full throttle the carbs are synchronised – it’s crude and not massively accurate but as there are no vacuum take off ports it ‘s the only way to do it. You then have to align the marks on the oil pump body but on this bike there was nothing to align the marks to!! I had to compare it with a photo in the Haynes manual, I have set it slightly oil rich to make sure, we can always wind it back a bit later when we have been able to test run it, which I can’t do yet as I still don’t have any mixture screws.

RD350LC old tyreAs I had the tyres here I decided it was time to fit them. It wasn’t a brilliant idea, in fact it’s one of the dumbest twat brained ideas I have ever had. It wasted many hours, caused a lot of bad language and some loss of blood. You see the first problem was that the rear wheel had a Metzeler tyre on it – it had plenty of tread but was bought in the sales by Moses and was over 2,000 years old – it was like iron rather than rubber. Probably originally fitted to a chariot – anyway, I digress. It had to come off but as much as I tried I couldn’t get the thing off the rim that had been it’s home since biblical times. I know, I thought, I will cut it off. That would not only get the job done but would provide a tremendous amount of satisfaction. Trouble was my grinder wouldn’t work so I had to take that to pieces to find out what was going on before I could progress. The switch was knackered so I bypassed it just so I could get this job done. A 1mm slitting disc did the job and the tyre fell off and with a demonic cackle I threw it on the scrap pile. All plain sailing now. Or not.

With the tyre off the inside of the wheel was cleaned thoroughly and I attempted to fit the tyre I soon gave up though and put the whole lot in the car and took it to the tyre place about 7 miles away. Sadly they didn’t have a valve to fit – it needed one of the old screw in types. So I left the wheels there, came home and found the only ones I had were fitted to rims. Never mind I thought, so I loaded them in the car and drove back to the tyre place only to be told they couldn’t fit them as their machine wouldn’t work on such narrow rims. So I had to come home again and ponder my options.

Fire seemed like a good one except those of you that know me will understand that my attempt to use fire last summer resulted in a 3 hour ambulance trip to the burns unit. I dismissed the idea, once bitten twice shy and all that.

No, the only option was to get out the levers and do the job myself. What a fucking idiot! I have had many bad ideas over the years but this one was the ultimate in stupidity. Two hours it took me and I couldn’t get the thing to seal to the point where I could get enough air in for the bead to seat. I thought I had got there once and the poxy schrader valve come loose and so I had to do it again. I did get there eventually but then I realised I had the front to do so I locked up the workshop for the night and got pissed instead.

Next day I had to face the joy of putting the front tyre on and I had an idea. At the tyre places they use a soapy sort of substance, I had used washing up liquid and water on the rear. I reckoned that some decent soap may make the job easier and as luck would have it I found the Wife’s Imperial Leather in the shower room. She wasn’t using it at the time so I relocated it to the workshop and set about giving the whole caboodle a damn good lathering. It made a massive difference and the tyre was on in less than 20 minutes. I wish I had thought of that yesterday!

If you are doing this job make sure the tyres are on the right way round. On the Avons that we fitted there are two arrows as they are mounted opposite ways round front and back. A bit weird but just make sure they are right before you commit.

So with both tyres on it was time to clean the rear hub components, refit the brake hub, fit the new sprockets and the superb DID x ring chain that www.wemoto.com had sent us. The front went on at the same time and everything went smoothly.

RD350LC NEW chain and sprocketsThe chain was adjusted up and everything tightened making sure the alignment was spot on. I like to use a vernier for this job particularly on this bike as the alignment marks were not particularly clear. A badly set up rear gives a horrible ride so it’s worth spending the time getting it right.

The chain was the sort that need the riveting tool to fit it, which is one of my least favourite jobs although a riveted chain is safer than the split link type. Remember to fit the 4 x rings supplied and to grease the new link to match the others.

For the first time in many a year the bike now sits on it’s wheels and everything looks splendid.

I ticked a couple of other very minor jobs off the list while I was at it – one exhaust stud was missing so I cut a length of stainless all thread to match the others. The new front brake light switch arrived so that was fitted, I also fitted the front mudguard.

The leak I had is now fixed, it’s been sat there 4 days and not a drop has appeared, which is nice. Sadly what isn’t nice is that the kick start mechanism is sticking. It’s not the sort of thing you can test on the bench but it is the sort of thing you can test before you fill the gearbox with oil. I will now have to drain it and take the right hand cover off to see what is going on in there. I am assuming either the nylon collar is damaged and I didn’t notice it or I haven’t installed it correctly.

I have to pick up the two mixture screws from Ian tomorrow so I will grab a spare starter assembly from his stash while I am at it. At least that way I will have the parts on hand if I need them.

I am desperate to hear this thing but need to sort the starter before I go much further.

As I had a bit of time left today and I want to get it started as soon as I can I thought it prudent to install the exhausts and the tank. The exhausts were a bit tricky because somebody has modified them at the engine end. They are supposed to have a flange on them that goes in to a seal that sits in the exhaust port but they had been removed from these for some reason, I hadn’t realised when I rebuilt the seating collar the other week. I got around it by fitting double gaskets which is not really ideal but it’s a lot quicker and easier and it will work just fine. I haven’t looked inside the tank yet but I just wanted to make sure that everything was fitting together correctly before going any further.

I will take the next photo outside the lighting in the workshop is hopeless and my camera isn’t the best.

RD350LC almost finishedSo before I could attempt a start I had to look at why the kickstart was playing up to do that I had to drain the 1500ml of fresh oil I had put in it and get the left hand side panel off. I spotted the problem straight away. I think I must have been tired, pissed or distracted when I put the starter assembly in the engine and had somehow got the small tension spring the wrong side of the receptacle that is cast in to the engine casing. I removed it, put it back together, tried it again and now it’s perfect, it engages and releases every time.

Next job was to fill up the engine with Motul coolant – word of warning these bikes have bleed ports on each cylinder, it’s a good idea to put bolts in them so the coolant doesn’t come straight back out again!! Our engine didn’t have them so I cut down some allen bolts and fitted a couple of copper washers, the engine hold coolant now.

So at last after 3 months of hard but enjoyable work it was time to kick er in the guts and see what happened. It is at this time I would love to tell you she fired up first kick but she didn’t. I gave her half a dozen goes but there was nothing. I checked the spark, it was still healthy so I took the top off the air filter and dribbled a little fuel in. Kicked her again and she burst in to life briefly – perfect – I knew it was a fuel problem.

The choke on this bike only works on one cylinder I felt the pipes and the left was warm the right was not so I suspected the idle circuits were blocked and the left was only firing via the choke circuit.

Getting the carbs back off is a real pain but what you can do is to loosen the jubilee clips on the inlet side and airbox side and rotate them 90 degrees so you can get the bowls off – sure enough both the tiny idle jets were blocked. I also noticed that when I mistakenly took the throttle cable retainers off I had put them on the wrong way round so the two bleed holes in the slides were blocked so I dealt with that at the same time.

Here’s the result of the second effort.https://www.youtube.com/watch?v=TbfUegzY5i4

I needed an air filter really but as I didn’t have one I made some out of some foam, I figured it would be good enough for testing and running one without an airbox makes my anus prolapse -it’s a really bad idea. It also makes a very big difference to the mixture. I would the screws in at the same time and checked quickly to see if oil was getting to the carbs – it was which was great news because I now felt safe to go to nearly neat petrol – I was still cautious though.

With all that done I gave her another prod and the results are here:https://www.youtube.com/watch?v=sEOthmqa8bY

I am delighted to report that even the temperature gauge works although the horns don’t if the are both wired at the same time 🙁 It looks like they don’t get enough current and I may have to fit a relay. We will go to the MoT with just one connected, that’s all you need for a pass.

So that’s it from me as far as the build goes, I will do one further short article and then it’s over to one Mr Scott Redmond to do a conclusion and remind us how articles should be written.

It’s been an absolute pleasure, I thank Scott and Ian at www.classic-motorbikes.net for letting me play with their baby. Massive thanks have to go to www.wemoto.com for supplying so many excellent quality parts in double quick time. Also thanks to the guys at www.venhill.co.uk for the brake pipes and clutch cable – quality parts like that make such a difference to the overall quality of the end product.

Half of me wishes it had been a full on balls out resto but there are too many of them in the world and they so rarely see the light of day. This bike is as honest as they came, it has a charm about it that only age can bring, who am I to deprive the world of such a thing?

Anyway I really hope you have enjoyed my ramblings and hope to be bringing you another project soon. Best and all that. Dave.

Article sponsored by Wemoto.

Article provided by David Powell of Boston Bike Bits.

Boston Bike Bits