The Zephyr Zone

Your Zephyrs, projects, purchases, in the workshop etc etc - will be interesting to hear what everyone's up to ....

Quick spin round the local roads today - first proper one for about 2 months, which was very welcome. Then it was home to start work on cleaning up a spare full set of standard exhausts and downpipes I managed to get hold of. Well pleased - cleaning up very nicely despite the surface rust. Going to take some time to complete this job properly, but I'm in no hurry. (good excuse to go hide down in the workshop, AND it gives me a good reason to go looking for a new 750 project to use them on - at least that's what I've told the Missus! )

It's too cold and wet in the Netherlands so haven't been doing much lately to my Zephyr750C1. But went to my garage today to spin it up and let it run for some 5 minutes. Man do I miss the decent weather!

750four wrote: gives me a good reason to go looking for a new 750 project to use them on - at least that's what I've told the Missus! )

Most people look for a new exhaust system for their bike. Think this is the first time I've heard of someone looking for a new bike for their exhaust system

P.S. I have done anything today, just sitting waiting for the overseas mail to arrive with larger main jets and shims for the needles. One size larger main jets was such an improvement I'm going to go up one more, and shim the needles one shim thickness (which is apparently equal to half a clip position if the needles had them e.g. 2 shims equals one normal clip position).

After dinner I'm going in the shed to clean up the gasket faces on my cylinder head and replace a valve shim. Then hopefully if I get the time I'm going to get the head back on

just seen the forecast for tomorrow .... more of what we've had for the last few weeks Today, however, is dry! 750 is warming up right now, and the 900 will be following the same route in about 30 minutes time. Just got to make the most of these 'weather windows' or I'll go nuts with cabin fever!

Weather is finally cool enough for comfortable riding (late December and early January were VERY hot this year) so took the bike out to test the jetting. Wanted to try the 'roll-off' testing method.

The methodology, you accelerate at full throttle, and at the RPM you want to test the jetting you quickly roll back the throttle a very slight amount. The theory, this small quick roll back causes the air fuel ratio (AFR) to go momentarily rich. If the bike actually accelerates or pulls harder when you quickly roll back this small amount then at AFR is leaner than the optimum power ratio. If the AFR is at the optimum or already rich, the engine will either just reduce in power or 'stumble'.

My D1 with one size larger jets than standard DEFINITELY accelerated when the throttle was rolled slightly back. It was very noticeable.

Naturally the true validity of the test will only be apparent after it is re performed with larger jets. But on the face of it so far the methodology seems reasonable.

interesting concept, freddy - will be keen to hear how it goes.

would you believe it - snow, ice and strong winds batter the country but down here at heathrow its cold, dry and sunny no prizes for guessing what me and the 750 were doing around lunchtime today ...

Finally got in my shed today after saying I was going in over a week ago I got side tracked by a Honda that was between my door and the shed I started tinkering with the Honda and one thing led to another and the Honda that wasn't running, but is now, passed its MOT last Friday
Well anyway, I cleaned up the gasket faces on my cylinder head and cleaned the rust out of my head nuts. There was a silver coloured residue from the old gasket on the underside of the head that was a right pain to remove so I thought I'd find an easier way than trying to scrape the crap of. I carefully sprayed a small amount of carb cleaner on it to see what would happen, 30 seconds later the carb cleaner had completely dissolved it all I had to do was wipe it off so I did the same for the rest of it, I was kind of disappointed that I did it so quickly
I took the head and nuts outside and blew through every single orifice with compressed air until every single bit of crud had gone.

My family were watching some TV Awards crap on the tv so I went back in my shed as I can't stand programmes like that. I put the new head gasket and O-rings on and refitted the head, it all torqued down nicely. Replaced the shims and buckets then put the cams in, I've loosely put the cam clamps in place for now and hopefully get them torqued down in the morning, it is 11pm as I'm typing this. It's been a good day as I didn't actually manage to break anything

haha! Glad I'm not the only one who can still be found in the workshop at nearly midnight!

My work this evening was a simple wipe-over with ACF50 to try and keep the worst of the damp/humidity off the 750 and also off the other bikes in the workshop at the same time. Surprising how quickly they'll start the 'metallic decomposition' process if you don't keep an eye on things, even when they're inside the relatively-protected environment of an unheated garage.