Tiesco
XS650 Addict
The other thing is the mp08 only has one connector for each coil instead of two for the point and condenser
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What have you done to your XS today?
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Wordman
XS650 Addict
You can use a GM ignition module to transistorize your points set up. Takes all the current off the points, and makes them last pretty much forever.
http://gpzweb.s3-website-us-east-1.amazonaws.com/Ignition/GPZheiModForPoints.html
http://gpzweb.s3-website-us-east-1.amazonaws.com/Ignition/GPZheiModForPoints.html
Tiesco
XS650 Addict
Gotta love Genral Motors.
The XS650 engine is what is called a 360 degree twin which means that the pistons go up and down together. When one piston is at top dead centre (TDC) and the plug fires to produce power, the other piston is also at TDC - but the exhaust valve is open and burnt combustion gases are being expelled.
The two spark plugs going off simultaneously are therefore just fine - one produces a power stroke and the other is simply called a "waste spark" - and lots of engines use a waste spark to cut down on the number of components in the ignition system.
Tiesco
XS650 Addict
I'm still a bit confused on how it would hook up. Not really seeing the complete picture. This is all very interesting stuff. Do you only need one contact breaker? The only reason there's two is because there's two separate coils right?
I think I need to relearn some of the basics of how the system works before I get into the more involved topics surrounding it
I think I need to relearn some of the basics of how the system works before I get into the more involved topics surrounding it
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Tiesco, the reason you need two contact breakers - unless you go to electronic but the principle is the same - is because the points are mounted on the camshaft. Which turns at half of crankshaft speed - because this is a 4-stroke engine. As Pete said, the pistons are rising and falling together but while one is on compression - ie valves shut - the other is on exhaust. The camshaft achieves this in half a revolution. During the next 180°, it reverses the opening and closing sequence, while the crankshaft and pistons perform another full 360° revolution. So you need to fire at least one spark every half-turn of the camshaft. Hence two contact breakers, or two pick-ups for an electronic system with sender plate on the cam, as with my Boyer.
Using one coil, as on my XS, means you fire both plugs together - this is the wasted spark set-up, because one cylinder is on the exhaust stroke as Pete said.
When Yamaha went to CDI, they used a pickup on the crank, so only one is needed.
You are right, this is interesting stuff, when I'm working on an an engine I just love seeing how it all works.
Using one coil, as on my XS, means you fire both plugs together - this is the wasted spark set-up, because one cylinder is on the exhaust stroke as Pete said.
When Yamaha went to CDI, they used a pickup on the crank, so only one is needed.
You are right, this is interesting stuff, when I'm working on an an engine I just love seeing how it all works.
Or a points cam with 2 bumps....
A vender sold exactly this.
Well it wasn't exactly exact so you could NOT get both cylinders to fire at the same time. (or so I've been told)
A vender sold exactly this.
Well it wasn't exactly exact so you could NOT get both cylinders to fire at the same time. (or so I've been told)
Tiesco
XS650 Addict
Old Okie
XS650 Enthusiast
After reading a few of the ignition posts my problem seems so simple.
How do you get the front brake light switch off the master cylinder??? Yes I am still doing brakes.
After 2 surgical procedures in February I have made no progress. Cold windy weather was
no help either. Yeah, I am a wimp. I spent most of my working life outdoors and now I avoid
the cold whenever I can.
How do you get the front brake light switch off the master cylinder??? Yes I am still doing brakes.
After 2 surgical procedures in February I have made no progress. Cold windy weather was
no help either. Yeah, I am a wimp. I spent most of my working life outdoors and now I avoid
the cold whenever I can.
I just took apart the carbs to clean... will I have to make adjustments or should they just go back to where they were ?
Sorry, Tiesco, not familiar with that set-up. The round attachment on the camshaft under the hex nut looks like it has two pointers - that's the reluctor?
Looks like that should work.
There's a small square window on the bottom, push the black tab in with a small screwdriver, it then slides right out..
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....and the tab you want to push-in is located furthest to the outside of the hole closest to the switch housing. You only make the mistake once. Mine was corroded into the sleeve, and thought I was adequately pushing the tab in far enough while gently twisting/pulling the switch out, only to destroy the switch. There was sufficient corrosion that prevented the tab from being pushed in far enough. Switch probably needed to be replaced any way (that's what I keep telling myself). Luckily, had a spare..
Tiesco
XS650 Addict
It's something I read on another forum. Someone took the pick up and reluctor out of a Toyota distributor and threw it in there. I thought it was pretty cool.
I just couldn't help it; have been imagining the bike with black trackers and swapping back to the black gauge buckets for months now, so I just ordered new bars and grips. I think for me the black shocks tipped the detail balance back to black. Also considering fork gaiters to complete the dark, rugged look. Also, I need to repaint my risers, as the first paint job I did wasn’t quite up to my standards. I think with black bars and a black crown, I’ll paint the risers gold. Pics when it’s all done. I do still love the buckhorns. This Sunday will be the two year anniversary of buying the bike, which was a couple months before I took the MSF course. Seems a lot longer ago than that. Even after only two summers I am beginning to understand why people are constantly changing stuff out on their bikes.
scrapmetal
XS650 Addict
moved myXS project into the corner to make room for my wife's Bandit 1200,
some of you guys may remember that I said goodbye to my XS1b project after Christmas last year for a 5 weeks job in Cape Breton?
Yeah, the 5 weeks have become over 2 months.
Now when I came home last Monday night , my dear wife had arranged a nice dinner and at the late hour she asked me for my biggest wish.
I did not say much, but immediately ordered the necessary parts for an update on her Bandit.
Galfer brake and clutch lines, flat tracker handlebar, bar end mirrors, new clutch and brake levers, race tech fork springs, Delkevic slip on pipe, oil filter and oil and some more little parts.
Reason for doing this? weeks ago she told me in a phone call that she have not enough time to drive her bandit his year and I can ride her bike whenever I want.
Feel a bit sorry for my XS, not cancelled, only moved, but the riding season is up soon
Cheers
some of you guys may remember that I said goodbye to my XS1b project after Christmas last year for a 5 weeks job in Cape Breton?
Yeah, the 5 weeks have become over 2 months.
Now when I came home last Monday night , my dear wife had arranged a nice dinner and at the late hour she asked me for my biggest wish.
I did not say much, but immediately ordered the necessary parts for an update on her Bandit.
Galfer brake and clutch lines, flat tracker handlebar, bar end mirrors, new clutch and brake levers, race tech fork springs, Delkevic slip on pipe, oil filter and oil and some more little parts.
Reason for doing this? weeks ago she told me in a phone call that she have not enough time to drive her bandit his year and I can ride her bike whenever I want.
Feel a bit sorry for my XS, not cancelled, only moved, but the riding season is up soon
Cheers
Attachments
I’m so confused. I have bs38 carbs ( I believe ) and I’m putting it all back together. Removed and replaced and each float with making adjustments and its at a perfect at 28mm. I didn’t have issues before taking them apart. I think I’m checking height correctly. The book is saying I should be at 24mm. That’s a big difference. Any help would be appreciated.
upon research I see my main jet is 135 and my pilot is 27.5... and that states late 78 bs38 carbs with a 24mm float level.
77 (which I have) has bs38 with a 122.5 main and 45.0 jet. based on this i'll say I have late 78 bs38s
im guessing I should just adjust to 24mm and see what happens. maybe this will also fix the "richness" ??
77 (which I have) has bs38 with a 122.5 main and 45.0 jet. based on this i'll say I have late 78 bs38s
im guessing I should just adjust to 24mm and see what happens. maybe this will also fix the "richness" ??
