68C

With a 180 degree parallel twin four stroke engine there is one exhaust pulse per cylinder every two revolutions of the crankshaft. If the exhausts are arranged as 2 into 1 it is possible by using equal length pipes to have these pulses follow each other evenly, one pulse will create a drop in pressure which will help the next pulse. This really only works well at one throttle opening and rpm, the length of the pipes determining the rpm. However we have 90 degree V-twin engines, the exhaust pulses are not evenly spaced, it is not possible to have a true 'extracter' exhaust system. I admire your desire to build your own system, you should be able build a lighter system.

Benders & menders.

Can't believe you really censored Mr Van Dykes name!!!

Its a bit like the difference between pilots and engineers, engineers wash their hands before they have a pee. Engineers keep their @#$$#! clean in the hope someone might want to eat their dinner off it. Welcome to the aviation world.

I am not too interested in the idle, just where I am in the fuelling map - throttle position and accurate rpm. I agree idle rpm not important, depends on the ambient conditions, how old the motor is and how much you dislike your neighbours on a cold morning.

Thanks Guzzimeister, yeah I got my first Guzzi, a T3, in '79. I just like tinkering. As an aircraft maintenance engineer I get fed up with having to do things exactly as the manufacturer states, have to keep fitting original bits you know will fail, not allowed to improve the design. The bikes keep me sane, then when my wonderful ideas fail I realise perhaps the aircraft designer is not so daft after all. Thanks emry, I tend to swap around between the MyEcu and the stock item, particularly since Paul's Guzzidiag software. The Optimiser does have this data displayed and I fitted a larger illuminated screen but still too risky to watch when riding. The much larger LEDs are brighter and easy to read. I am just messing around comparing A/F ratios between the two devices whilst I move around the fueling map, can't really explain why I want to do it other than interest and to see if I can. I like the idea of counting the injector pulses, no need to differentiate between the regular 48 tooth pulses and the missing pair. I believe the ecu output to the Tacho varies the frequency, again not too sure how to handle that. Thanks Kiwi_Roy, the intention is to be able to read it while riding, perhaps I could use the street lights and a mirror! You mention removing the alternator cover, I guess you don't have the front balance pipe.

I am thinking of making a digital tacho that I can clip onto the bike when doing engine tuning, the stock item does not seem too accurate. I intend to use an Atmega328 Microcontroller 'Arduino' based project. I will use a 14mm high 4 digit LED display that I can attach to the top of the instrument panel with Velcro. I have already made a display that shows the throttle position. As the bike has a test lead (wiring diagram item 58) built into the loom connected to the timing sensor I was hoping to use this as my signal. I understand the timing sensor has a 48 tooth wheel with 2 teeth missing, as the timing point, and that it is on the end of the camshaft so rotates at half engine speed. Has anyone tried this before or have any advice on what the nature of the output to the tacho is, I assume it will be digital as it is supplied by the ecu. Why am I doing it, mainly as a hobby interest but also cost. The microprocessor costs about £4 and the 4 digit display free from an old Sat. TV box. or about £2.

One less oil seal to fail and no dirt/water getting into the alternator.

Ye Gods that takes me back, had one to satisfy my craving for a non Harley v-twin. Fully enclosed rear chain was a big attraction. Brand new they were selling for amazing knock down prices. Yeah, fully enclosed chain a great idea, unless you are lazy and can't be bothered to take the covers off to look at it. Mine broke - punched a hole in the casing and left me stuck on the M3. Managed to cut a piece of wire out of the fence and bodged the chain for a slow crawl off the motorway, How I laughed.

I have not used any RTV sealants for the last 20 years since I used it on a Yamaha TR1 v-twin. A small blob on the inside of a casing came loose and blocked the oil feed to the cyl head which trashed the camshaft. If you must use it just use the barest amount. Silicon goes rather soft and swells when exposed to oil for a long time, perhaps this is a good thing as it may help seal but a bad thing if too much has extruded on the inside. I prefer Hylomar, orange or blue - not the old fashioned red type. Lycoming piston engines, as fitted to most small prop aircraft, have no gasket between the crankcase halves. They rely on a thin film of Hylomar onto which is laid a single thread of ordinary sewing cotton. When you unbolt one years later the cotton has crushed flat, I believe it helps hold the Hylomar from squeezing out. I use this technique on all my old Brit bikes.

Make sure you have reconnected all the earth leads to the battery and that none of the terminals on the end of the wires are damaged. .

Oh dear, the cycle has started.

I had a Norton Commando that would always play up, until I tried to sell it when it performed perfectly so I hung on to it, A few years later it would piss around so up for sale and again ran perfectly. This went on for fifteen years until I got the message. I still have the bike forty years later,

Are you asking about the detachable stands you use in the garage or permanent fitted stands for use on the road?

Hey DonG, where is your 850cc T3, it was about the first widely sold Guzzi in the UK, I mean the Roadster not the Cali or Le Mans. They were too dear. T3s still crop up although many are converted to 950 similar to the G5. I did mine but in truth I never noticed any real change in performance. What happened between 1978 and 2000, kids?

You really can tell a lot from a plug chop, in particular with two stroke motors as they tend to seize if too weak. For best results warm the motor then ride out to your chosen quiet road to do the test, fit a new clean plug and carry out the plug chop. A search of the internet under 'plug chop' will give plenty of advice and photos of plugs in various states. Be carefully, don't be too obvious about what you are up to, at least not in the UK, as road testing may invalidate your insurance and may be considered illegal.

Back in the day doing a 'plug-chop' was the usual way of checking the fuel air mixture, before lambda sensors etc. It simply entailed riding the bike at whatever throttle setting you were interested in, I.e. Half or full, preferably up a slight incline to load the motor for a minute or so then simultaneously hit the kill switch and pull in the clutch. The idea is the plug colour will indicate the mixture at that throttle setting. If you just slow down pull over then check the plug you get the colour (and so the mixture) when it was at idle when you stopped. It was always a fun thing to do especially if you were a bit uncoordinated as of course pulling in the clutch too early had the revs soaring and pulling it in too late meant the back wheel could lock up,

Back to Pirelli tyres, I just bought a new Angel ST, has "Made in China" printed on it. is this the usual place of manufacture?

By definition a dielectric is a non-conductor, so you don't use it anywhere that you want electical current to flow. You do want to use it where you do not want electrical flow. So, inside the sparkplug cap is a good place to use it as it will help exclude moisture and will not conduct the spark energy away. it should not be used between bolted up earth points, contacts or the pins on the electrical plugs. Ideally the bolted up joints and plug connectors should be chemically clean and free of corrosion, once bolted up or plugged in it is now safe to overlay with dielectric grease. Silicon is a dielectric so most silicon greases are dielectric. I understand there are special silicon grease compounds with conductive fillers used in industry for specific purposes such as the interface between an aircraft skin and antennas although I have no experience of them.

I cut back the insulation a bit and soldered on two wires then wrapped them in self amalgamating tape. Then put female crimps on so it's now easy to check. (Self amalgating tape is like insulation tape, you have to stretch it a bit and then wrap it on, somehow it bonds to itself over a few hours)

Hi Bill, I know I said I was enjoying reading this thread - was'nt looking for you to make so much effort to entertain us though. Glad your not badly hurt, bikes can always be fixed. Loved the slides how, you would have to be up at 5.00am on a summers day to find empty roads like those in the south of England.

I can understand not using oil with friction modifiers in bikes with wet clutches but cannot see that would be a problem with our dry clutch bikes.

Going well off thread now, if I remember we night stopped in France, Corsica, Italy, Greece and Crete. Cruised at 98knots but with a headwind watched articulated lorries overtake us down the motorway to Lyon - would have been cheaper and quicker to have landed on one!

We don't need anything for that 'duty', our women are always ready. Lets face it, you never heard of a Brit getting into an open boat and rowing across the North sea to get to the Viking girls.

No, just got to go the engineer training schools. Did ride in a Bell 212 from the UK to Cairo once and had several trips in the HS125 biz-jet to Nigeria - the six months in Lagos took the shine off it though.