OMG it's already spread across the pond. Close the borders!QUICK - one of you guys in Britain - get up there to the Scottish Borders and GET Raymondo SOME HELP!!!
He's caught a bad case of Mailmanitis!!!
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Miss November XS2 tribute
- Thread starter Raymond
- Start date
Prepare to be assimilated, resistance is futile! 
Careful. The sun may reflect off it and set the house on fire. Just gotta wear shades to look at your bike.
Agreed. I once set a chrome cover on my seat in the sun. The angle of the sun reflected like a laser beam off the chrome up onto my backrest. Looked up after wrenching a bit and saw smoke rolling off my back rest. Bummer....Burnt a whole clean through in a matter of minutes.
Now Pete, you know I could never even approach Bob's standards!
Well, that is what the second guy to build an airplane said about Orville and Wilbur - and now, we've been to the moon. Once guys get going on stuff...and the competition starts...who knows where it will lead....
Serendipity:
The postman delivered three packages & envelopes today - two 22 mm open-ended spanners, some oil feed copper washers and some drain plug ones. All I need to put the Orange one back together.
The postman delivered three packages & envelopes today - two 22 mm open-ended spanners, some oil feed copper washers and some drain plug ones. All I need to put the Orange one back together.
Super!! Keep us posted Raymond.
Did you get the oil feed tubes straighten out?
Did you get the oil feed tubes straighten out?
Well, people said to bend using thumb pressure. They must have stronger thumbs than I do. Used gentle force with pliers and bent them enough to fit where they should, but the sharpest bend resisted so the part isn't fully symmetrical. Will put up with that. If fussy, would raid the spare engine. But to be honest, the thing that would worry me most is the pipe splitting in service. Therefore didn't want to use a lot of force and strain pipes or joints.
Many years ago, the oil drain plug - lower end of the front down-tube - fell out of my SR500 as I was going down the hill into Kirkaldy. First warning was that my foot slipped off the gear change lever. Thankfully, I heeded that warning, stopped and investigated - there was already oil on the rear tyre . . .
Kirkaldy has a railway station - bike and I went home by train that day.
Good call. Those horizontal tubes are hidden under the fuel tank anyway.
Oil feed has been re-fitted, with six new washers in three sizes, liquid PTFE on threads at the union, banjos torqued down. Always feel like a proper mechanic wielding the torque wrench.
Between these two images was an awkward interlude. Tried to pump the lift up to release the safety bar. Nuffin doin'. Not gonna move. Nada.
Well, I can hardly leave the bike stuck like a hen up a tree so I used a Heath Robinson (worth looking up if you've never heard of him) arrangement of wooden blocks, a car tool-kit scissors jack at the rear and a bottle jack at the front. Took the weight with those then let it down little-by-little.
When I moved the lift, there's just a few drops of hydraulic fluid on the floor. Anybody know how to mend a hydraulic jack?
The good news is, starts just fine. Runs with no nasty noises. No oil leaks yet.
Now just need to go and buy some essential supplies . . .
Fill it up with Maple syrup !
...and I can help with that!
Thank you, Machine. And Pete (we crossed in the post). Ahem, where was I?
Quick test run, only eight miles, bike running well, apart from that poppin' and bangin' on closed throttle.
Took the plugs out and I'm slightly puzzled:
Don't know how to read these. Is the bike running lean? The centre electrode is not covered in white ash, it just looks clean. Well, these were new plugs about 20 miles ago. There's some soot around the edge and the curved electrode does have some whitish residue.
Quick test run, only eight miles, bike running well, apart from that poppin' and bangin' on closed throttle.
Took the plugs out and I'm slightly puzzled:
Don't know how to read these. Is the bike running lean? The centre electrode is not covered in white ash, it just looks clean. Well, these were new plugs about 20 miles ago. There's some soot around the edge and the curved electrode does have some whitish residue.
Yes, they do look a tad lean. You want the strap to be a light gray or brown, not white. The soot around the edge is normal. The porcelain center should remain clean but will color lightly over time. Yours looks very white, but maybe it's because they're so new. But that popping you have is also a lean indicator. I know your mufflers are aftermarket, what about the intake? Stock airboxes still or pods? You might benefit from bumping the mains up one size, maybe the pilots too. What are your mix screws set at? Stock spec for your carb set is 2.25 turns out but when mine was nearly stock, it liked about 2 5/8 turns out better.
RonXS
XS650 Addict
Jumping in late... I like that color Raymondo!
I am not a carb expert but I do know a bit about what it takes to make engines run consistently.
When the OEMs design and test new engines, they have whole squads of engineers who specialize in "calibration" and these guys test EVERYTHING and develop special mathematical models of fueling, ignition variables, coolant flows etc. etc. to make the engine run just right under all conditions. That requires modern engines to have all sorts of sensors measuring what the driver wants, what is going in and what is coming out - and the engine systems adjust everything on the fly to make it all good. This is called closed-loop control because the "loop" between inputs (air/fuel/temperatures/loads/throttle position and rate etc.) and outputs (exhaust temp/O2 content and power demand) is closed and a computer is constantly doing the math to adjust timing, injection pulse width and number....etc. so that you get what you want from sea level to 12,000 ft on cold, hot and in-between days, pretty much regardless of fuel quality.
In contrast, our nice old XS650s are totally open-loop with very simple (i.e. primitive) carburetors and no control whatsoever on the ignition or anything else. Basically, you twist the grip, the throttles open because the cable(s) pull on them....and the engine does whatevertheheck it likes.
Soooo....I always take the jet sizes and screw settings as a starting point, not a gospel set of rules to be followed. A little warmer day, a little lower ambient barometric pressure, a slightly more humid or dry day, a little more stale or less stale fuel, a spark plug that is new/old/dirty....and everything changes a little. That is part of the fun of riding an oldie - the tinkering and the mystery of "what are you going to get today" - IMO.
In many respects, it is sort of amazing that they run as well as they do over such a wide range of conditions.
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Gentlemen, once again thank you for your interest!
5T, the bike runs stock airboxes. You mentioned the mix screws before so I'll take a look for those and check how they are set, maybe adjust. You also suggest a size up on the mains - would raising the needles a notch perhaps be worth a try first?
Ron, the bike looked very different a year ago - take a look here http://www.xs650.com/threads/before-and-after.55250/page-2#post-607102
post #38 for the before and after. I bought the bike with the faux Triumph Thunderbird look but it had not been done very well. Read all about in this here thread, but if you do best skim and just look at the pictures as this is quite a long thread now. Has it really been just a year?
Pete, words of wisdom as always. A bit of tinkering is probably to be welcomed, involvement with the bike and so on. I might just about have reached that state I always intended when buying an old bike - Triumph TR6 650, then the XS on the rebound - owning a proper motorbike that looks and feels like a bike ought to and which I can jump on and use whenever I want to with just a bit of fettling, fiddling and routine maintenance required.
5T, the bike runs stock airboxes. You mentioned the mix screws before so I'll take a look for those and check how they are set, maybe adjust. You also suggest a size up on the mains - would raising the needles a notch perhaps be worth a try first?
Ron, the bike looked very different a year ago - take a look here http://www.xs650.com/threads/before-and-after.55250/page-2#post-607102
post #38 for the before and after. I bought the bike with the faux Triumph Thunderbird look but it had not been done very well. Read all about in this here thread, but if you do best skim and just look at the pictures as this is quite a long thread now. Has it really been just a year?
Pete, words of wisdom as always. A bit of tinkering is probably to be welcomed, involvement with the bike and so on. I might just about have reached that state I always intended when buying an old bike - Triumph TR6 650, then the XS on the rebound - owning a proper motorbike that looks and feels like a bike ought to and which I can jump on and use whenever I want to with just a bit of fettling, fiddling and routine maintenance required.
Yes, I think you're very close to having this thing dialed in, just some fine tuning left to do. Yes, you could try raising the needles a step. That would richen the midrange and the upper portion of the idle circuit. It should definitely add some color to your plugs too. The needle setting has a big influence on plug color because you run in that range most of the time. However, you may encounter one issue with your particular carb set .....
Your carb set came stock with a #135 main, the largest used in any 650. To make that work, they reduced the needle jet size to a Z-2. Earlier carb sets had bigger Z-6 or Z-8 needle jets paired with mains several sizes smaller. But, even though they reduced the needle jet size in your carb set, the upper midrange is still right on the verge of being too rich. Set the needles richer and it may be. This would cause break-up or stumbling in the upper midrange under heavy throttle applications, say in the 3500 to 4500 RPM range. To test for this, in 2nd or 3rd gear starting at around 3K RPMs, grab a big handful of throttle, or whack it wide open, and run on up to about 5K RPMs. Watch for break-up or stumbling. If you get any, that's telling you your richer needle setting is too rich.
This is how you normally tune these carbs for mods. You start by increasing the mains one size at a time until you start getting the upper midrange break-up I've just described. When that happens, you lean the needles a step to fix it. Now, you can continue to increase the main jet size but that usually brings the upper midrange stumble right back. So, when it initially starts to happen, that's a pretty good indication that you've gone as big on the mains as you can with that particular carb set. Now, I realize you're not increasing main jet size but I think setting the midrange richer is going to have pretty much the same effect on that upper midrange or midrange to main circuit transition area - it will become too rich.
Your carb set came stock with a #135 main, the largest used in any 650. To make that work, they reduced the needle jet size to a Z-2. Earlier carb sets had bigger Z-6 or Z-8 needle jets paired with mains several sizes smaller. But, even though they reduced the needle jet size in your carb set, the upper midrange is still right on the verge of being too rich. Set the needles richer and it may be. This would cause break-up or stumbling in the upper midrange under heavy throttle applications, say in the 3500 to 4500 RPM range. To test for this, in 2nd or 3rd gear starting at around 3K RPMs, grab a big handful of throttle, or whack it wide open, and run on up to about 5K RPMs. Watch for break-up or stumbling. If you get any, that's telling you your richer needle setting is too rich.
This is how you normally tune these carbs for mods. You start by increasing the mains one size at a time until you start getting the upper midrange break-up I've just described. When that happens, you lean the needles a step to fix it. Now, you can continue to increase the main jet size but that usually brings the upper midrange stumble right back. So, when it initially starts to happen, that's a pretty good indication that you've gone as big on the mains as you can with that particular carb set. Now, I realize you're not increasing main jet size but I think setting the midrange richer is going to have pretty much the same effect on that upper midrange or midrange to main circuit transition area - it will become too rich.
5T - very clear explanation.
I don't have a lot of carb tuning experience. Back in the days when bikes had carburetors, I'm thinking 70s and 80s, occasionally had to sort out a problem on, well, Yamaha SR500, Norton Commando, Kawasaki Z1. Lots of confab with fellow students/bikers/tinkerers. Would maybe invest in a new set of jets or needles which was a big expense when you're an impoverished student. But I digress.
Today, had a look at the carbs and identified the mixture screws. Both were set to standard 2¼ turns out, so I have set both to 2½ as a first experiment. Itching to go out for a test run and see if that has any effect on the back-firing. But. Bloody lock-down.
Maybe tomorrow . . .
I don't have a lot of carb tuning experience. Back in the days when bikes had carburetors, I'm thinking 70s and 80s, occasionally had to sort out a problem on, well, Yamaha SR500, Norton Commando, Kawasaki Z1. Lots of confab with fellow students/bikers/tinkerers. Would maybe invest in a new set of jets or needles which was a big expense when you're an impoverished student. But I digress.
Today, had a look at the carbs and identified the mixture screws. Both were set to standard 2¼ turns out, so I have set both to 2½ as a first experiment. Itching to go out for a test run and see if that has any effect on the back-firing. But. Bloody lock-down.
Maybe tomorrow . . .
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