Inconsequential ramblings of an Old Git

[mangocrazy]

The stripdown has started. I decided that the steering head bearings were shot, based on juddering under braking and what felt like the forks topping out over sharp speed bumps, making a really sharp clunk. So that was the first thing to fix, giving me more time to stew over the electrical problems. A pair of Koyo taper roller bearings and dust seals were ordered off eBay, and then it was a case of getting the bike on the skylift and peeling the onion, exposing layers of stuff that needed to be removed. This is the early stage, with the front wheel out and top and side fairings removed:

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I made a start in my cunning plan to run an additional earth to the front end of the bike, but realised I didn't have any green cable in a suitably chunky gauge. But I did have some yellow cable of the right size that I'd bought to rewire the Ducati's alternator, so I used that instead. What are cable colours, anyway? I've connected the rear frame earthing point to the headstock subframe mounting point and will then run a cable from that point to a Wago multi-connector which will take feeds from indicator and headlight/sidelight earths. This should provide more than one source of ground to the problematic electrics.

I also made progress on the head bearings - I got the bottom yoke and top bearing mount off and gave them to someone else to remove the bearings. I am a master of delegation. Thanks to the helpfully provided indents in the headstock it was fairly simple to get a drift onto the top and bottom bearing sleeves and tap them out. Only very minor violence was required. Once out, it was clear that the bottom bearing in particular was not healthy. I could feel pits and hollows with a fingernail in the bearing cups/sleeves, so replacing the head bearings is definitely a Good Move. Not sure how it wasn't picked up in the MoT, though. Anyway here's a picture of the mechanical chaos that now greets me when I enter the shed:

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[mangocrazy]

Taper roller bearings arrived at lunch time and the bearings and dust seals were duly taken to the bike shop for them to fit. The old bearings have been removed and the completed parts should be ready tomorrow. A big shout out to these guys - Manhattan Motorcycles on the Chesterfield Road. They know their stuff, they're helpful, friendly and are happy to give advice when asked. Can't fault them.

The headstock recesses have been cleaned and degreased and the oiled bearing cups pressed in using a home made special tool, which isn't that special at all. It comprises two circular steel blanks that I had machined up that are fractionally smaller than the o.d. of the cups and which have a hole in the middle to take a length of M12 threaded rod. Nuts and washers are wound on at each end and tightened up gradually, forcing the bearing cups into place. It's a low tech, manual version of a hydraulic press, basically. I've left the plot tensioned up over night just to convince the cups that resistance is futile.

[KungFooBob]

I've never been in Manhattan, I did ring them when I was looking for a Bullet to see if they had any 2nd hand ones in stock, they didn't but the bloke was nice enough.

The shop looks tiny, someone told me it goes downstairs or something?

[mangocrazy]

I've never been in Manhattan, I did ring them when I was looking for a Bullet to see if they had any 2nd hand ones in stock, they didn't but the bloke was nice enough.

The shop looks tiny, someone told me it goes downstairs or something?

I think there may be a cellar that's part of it (store room/stock room?). The workshops are out the back and the showroom is pretty small. But they all seem to have a genuine interest in bikes, it's not just a money-spinner and the non-glitzy nature of the shop bears that out. It just strikes me as an honest place run by people who really care about bikes. They do have plenty of REs in stock, and are an RE dealer.

[mangocrazy]

Front end is now reassembled with new taper roller head bearings and the steering feels so much nicer - taut and smooth. I guess they'll need a slight adjustment once they've bedded in, but it's made a big improvement.

I've also run a secondary earth to the head and side lights and indicators, and things now work. Sort of. Something funny is still going on with the headlight and side light - can't get the side light to work and dip and main beam give the same result. I'll be checking out the switchgear next. I've also spent a lot of time getting the cable routing correct around the headstock and front fairing mount and have replaced the tired old bullet connectors with latching two way connectors for the indicators (which work, thankfully).

Still haven't tried starting it. That can wait until tomorrow...

[mangocrazy]

It starts. So that's a major plus. I'm still checking out the minor electrical oddities.

[mangocrazy]

We now have dip and main beam working correctly and the side light bulb is en panne/gefukt. I can truthfully say I am not sure what it was that fixed the various issues, but I don't think that providing a secondary good earth will have hurt. Neither did the liberal application of spray switch cleaner/lubricant to the handlebar switchgear. If nothing else, the switches all feel a lot more precise and nicer to use. And I dicked about with every major bunch of electrical cables/connectors in the steering head/fuse box area disturbing them all with my swearing, which must count for something.

If I was still at work and I'd 'solved' a similar problem, my boss would be niggling at me to 'run more tests' so I could conclusively establish the exact cause. But I'm not, I've retired and he can go fuck himself.

Time for either a beer... or a beer.

[mangocrazy]

And to double the good news, Dave Whattam (Mutts Nuts) just rang me up to set a date for him to put my 350LC on his dyno and get the jetting right. A week today and my LC should be better than it ever has been in its life...

[mangocrazy]

I put the replacement top Falco fairing into the paint guy for filling/sanding/priming/paint back in February. It's finally made it into primer. I'd like to say I'm ecstatic.

But relieved would probably be closer to the mark.

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And I just found this, which nicely positions Falco owners in the Aprilia spectrum...

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[Supermofo]

Taken since February! Wow. He better be good

[mangocrazy]

Taken since February! Wow. He better be good

Yes. He was recommended to me by a guy who knows his stuff, but 6 months to get a panel into primer is taking the piss a bit... He did have to do a fair bit of repair work, but...

This is how I handed it over to him:

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[mangocrazy]

9 a.m. saw me rocking up to Dave Whattam's place in West Yorickshire with my LC in the van. Half an hour or so later it was strapped down onto the dyno and Dave was doing some initial checks. First thing was to check the state (and presence!) of the air filter and make sure it wasn't over-oiled. Then he checked the setting of the oil pump, and was pleased to see it had been recently overhauled by 'Arrow' on the RDLC Crazy forum. Then it was time to have a look at the plugs and after that time to warm the engine up and do some exploratory runs.

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The first dyno runs confirmed what I knew to be true - that there was a black hole in the powerband just after 5000 revs that didn't clear umtil gone 5500 rpm. Even before he'd checked the Air-Fuel ratio, Dave could tell it was running very rich, partly due to me running a very conservative (i.e. big) main jet size. Each run Dave did, the top end improved as it burnt off carbon deposits brought about by running in mileage. So now it was time to pull the carbs off for inspection and jetting changes.

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I couldn't believe how quickly Dave had the carb broken down to its component parts. On both carbs there was loads of crap in the emulsion tube chambers, and also behind the brass balls, The float needle seats were badly worn on both carbs, allowing the fuel level to be too high and contributing to the over-rich mixture. Dave also went down two sizes on the main jets (220 down to 200), but left the needles at the mid position and verified that the needles were correct and undamaged (which they were). Then it was time for the 'after' dyno run. To say I was pleased with the results was an understatement...

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[Yorick]

I was running 310 main jets when racing. Needed more wind

[mangocrazy]

I was running 310 main jets when racing. Needed more wind

You'd have been running either an open airbox or no airbox, I guess. And making closer to 60 bhp, as well. My LC is essentially standard.

[Le_Fromage_Grande]

From memory 220 is standard, and Yamaha set them up so they wouldn't hole pistons, 200 is probably correct for summer, but would be a bit lean in winter.

I think I ended up with 260s in mine, running Allspeeds and pod filters, ended up with Ledar emulsion tubes to make it run right.

BTW very early 350s are different to later ones, they have different carbs and Yamaha tried all kinds of things to get them running right.

[Yorick]

I was running 310 main jets when racing. Needed more wind

You'd have been running either an open airbox or no airbox, I guess. And making closer to 60 bhp, as well. My LC is essentially standard.

Yup. We all cheated. We only worried when somebody cheated better than us

[mangocrazy]

From memory 220 is standard, and Yamaha set them up so they wouldn't hole pistons, 200 is probably correct for summer, but would be a bit lean in winter.

I think I ended up with 260s in mine, running Allspeeds and pod filters, ended up with Ledar emulsion tubes to make it run right.

BTW very early 350s are different to later ones, they have different carbs and Yamaha tried all kinds of things to get them running right.

Yeah mine is a very early (first batch) 1980 model and the fuelling has always been A Bit Shit. So I took Gerry Pell's advice and got a pair of 31K YPVS carbs. Dave reckons he always sets them up slightly on the rich side based on the AFR he sees, so I'd be surprised if it wasn't safe all year round.

Having said that, when the temps drop below about 12-13 deg C I'm unlikely to venture out anyway...

[Le_Fromage_Grande]

The early YPVS carbs are much better than LC carbs, I don't know why because according to Mikuni they're all the same.

The late YPVS carbs with power jets are a bit shit btw.

I think a YPVS is 240 main jet standard, but they run pretty rich, my one had a Stan Stephens stage 2 tune and Lomas pipes and still ran standard jets for a good 3000 miles with no problems, then I sold it, which is something I regret.

[mangocrazy]

Yes, I had a PV motor with power jet carbs in my Hejira 'special' and I could never get it to fuel properly. I've heard no end of people say they're a 'mare to set up. One thing that doubtless contributed to it was not realising that YPVS carbs had a spigot for the hose to connect to the vacuum fuel tap which needed blanking off if a standard gravity fed tap was used. I only found out about this a couple of years ago...

My LC has early non-power jet YPVS carbs, I'm glad to say.

[Demannu]

43hp !!!
Time to buy some of these

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Just shows what a good job Yamaha did with the Elsie!