Miss November XS2 tribute

[Rasputin]

Gentlemen, once again Thank You to all for your help on this!

It is much clearer to me now what the starter circuit and starter relay need. The wiring I had to start with had been modified and I've changed it a lot more so I was feeling a bit out on my own. But Rasputin, yes the white wire from BB was to the coil mount not the spade connector.

The black ground from the other coil mount used to go to a horrible mess of soldered (soddered?) black wires which I have replaced with bullet connected wiring from most of the earths on my diagram (not the neutral switch which grounds straight into the engine) and led to two ring terminals at the head steady, so there is still a connection from the head steady to the coil mount. Not too sure that all is correct, but . . .

Pete, I will take the safety relay off today so will have a wee look inside and clean it. I need to join a new wire from the kill switch to give a power feed as Jim suggests. Quite probable that's why the starter motor is inert.

Jim, I will open up the l/h switch cluster and check the earth wire which I think is the one connected to the headlamp bulb. Will check if/how this routes to earth.

And Pete, thank you for


Need a bit of encouragement sometimes.

On my XS the safety relay had been altered by changing the wiring connections rendering it inop.
I delved into it removing the cover, it was full of rusty dust, I cleaned it all out and cleaned up the points, put the wiring back as it should be and it worked as it should.

 

[5twins]

I'm in favor of the starter portion of that relay and think it's a good idea, but the headlight auto-on relay Yamaha stuck in there on the later models, not so much. I prefer to have full control over the headlight on-off function myself.

 

[Raymond]

Unfortunately, still won't take any throttle. Limped up the street and back again and any throttle just kills the engine. Idles nicely and a blip of throttle sends the revs up. But only so far. Gets to 3,500 and give more throttle to rev further? Nothing doing.

Can't believe it's carbs as the bike was running better than this a few weeks back.

Have been in the garage. Despite unwillingness to think it might be the carbs, have dismantled them. 135 main jets, 27.5 pilots, 502 needles.

And the good news (bad news?) is -

have found a split in the rubber diaphragm on the r/h slide. It's only a small split, maybe 5mm long and you can't see it unless pull the rubber to open the gap. Too small to show up in the photo. Looks like the diaphragm has been pinched between finger nails or something.

My question, is this split sufficient to explain the bike running badly?

 

[peanut]

..

 

[Raymond]

I was going to reply before I suddenly remembered that i cannot give advice anymore on this forum

Sorry pardon? Your advice has always been very welcome, Peanut!

Have been looking for replacement carb slide. CMS list the part number 2F01494000 but none in stock. Yambits list a carb slide but state that it is not interchangeable with 1978-79 US carbs as the needle retainer differs. XS650.de list the carb slide but now I'm in doubt about compatibility.

 

[Jim]

I'd say that's most likely your problem. One way to tell for sure is to "fix it" with a little fuel resistant RTV. A very small amount so as to not affect it's ability to flex. If that's your culprit, they're easy enough to replace without removing the carbs again. Did you do a "drop test" before you disassembled the carbs?
Edit: Try a little cellophane tape first. It'll be easy to replace and you won't have to wait for the RTV to cure. If that's it, pull it back out and try the RTV.

 

[peanut]

...

 

[Raymond]

yes there are 2x different types of BS38 carbs your carbs are the earlier model. BS38 76-77 as you know
The later BS38 78-79 carbs also have different needle jets and jet needles and the jet needles are fixed in the slides with a different assembly none of which is interchangeable except the diaphragms.

Oh dear! No,I don't know which type of carb is on my bike. It's a 1978 bike (I think) and I have just been on Heiden Tuning and ordered a carb slide. So now it's fingers crossed and see if it's the right one . . .

 

[peanut]

...

 

[Raymond]

This is what my slide and needle retainer looks like:

So I guess mine are the later type? I wouldn't be surprised if they have been swapped at sometime. But as said earlier, Yambits state that the slide they sell is not interchangeable with US 1978-79 parts. I think my bike is a Canada model and have no idea whether the Canada bikes are same as US or a distinct spec.

I am now sightly hopeful that the bits from Heiden will be correct. flubberfluberflubdub

 

[peanut]

...

 

[peanut]

..

 

[5twins]

Raymondo, peanut's advice is often frowned upon because it's usually wrong, as is the case once again here. You do have the correct later style BS38 carbs for your model. The big "tell" is the internal float bowl vents. Those are the 2 round ports at 3 and 9 o'clock around the outside edge of your intake bells .....

More "tells" are the float bowls with no internal overflow pipe and no drain nipple for it on the bottom of the bowl, and the later type slide with a spring-loaded needle retained by a snap ring. All the jetting you found is also correct for the '78-'79 carb set.

Yes, your torn diaphragm was responsible for the bike not revving any higher than 3 to 3.5K. That slide wasn't able to lift because with the tear, a vacuum couldn't be generated above the diaphragm to "suck" it open. If the diaphragm/slide assembly you ordered is for the '77 and older carbs, it's not going to work for you.

 

[5twins]

I should also mention that it appears your needle has been assembled incorrectly. The thick plastic spacer ring should go on top of the e-clip, thin washer and spring under it .....

This may also have been adding to your problems. Assembled as yours is, the needle wouldn't be sitting at the proper height.

 

[peanut]

My apologies Raymondo for sending you astray my sight isn't as good as it once was with this blasted Diabetes and I completely missed those tiny vents .

5twins is correct . Now that I have looked more closely at the images of the carbs I can just about make out the 2x extra vents in the mouth of the venturi as 5T points out. They are the easiest way of telling the 2x models apart . That now explains why you have the later style slides in the carbs .


Ignore everything I have said and just go with 5T's advice I will remove my posts in case they mislead anybody

 

[peanut]

Raymondo, peanut's advice is often frowned upon because it's usually wrong, .

.

5Twins your statement is not only factually incorrect , it is also in my opinion an unnecessarily malicious comment to make of a fellow xs650.com member who is clearly trying to help another member and xs650 owner.

There was no need to lambast me for what was clearly an innocent mistake ... all you needed to do was to draw my attention to the error so that I could edit my posts accordingly.

I have seen you make various mistakes and technical errors over the years... but I have never publicly belittled or embarrassed you for making them .....
That is the big difference between us

I used to really respect you ..........and have a high regard for your xs650 knowledge and experience when I first joined this forum

Regrettably your behaviour towards me and others on the forum has revealed that your personality and character to be considerably less exemplary than your technical knowledge

 

[Raymond]

Obviously, there are complications caused by Yamaha in their wisdom changing the carb type fitted to the XS650 - from the caution given on the Yambits site I suspect that the change might have reached different markets at different year models? Typical of me not to be aware of this until too late but it appears I have got away with it as my carb bodies appear to be 78-79.

Got to be patient till new slide comes from Holland. And then, who knows . . .

Onwards and upwards.

 

[Raymond]

Still sitting waiting like a gooney bird, as I'm sure nobody in the United States says, for new carb slide to arrive from the Netherlands.

Took another look at the indicators (turn signals) and one problem is that the attachment method is naff. They are chrome, bullet-shaped mini-indicators and I could live with the looks but don't think they were made for an XS650. Plus they aren't working right now and the wiring is dodgy so decided to replace. Got some suspiciously cheap LED replacements on order together with an LED-type flasher unit. 'Universal' fit, which promises lots of fun.

Have also lashed out and ordered some genuine Yamaha headlamp dampers and collar pieces.

Each time of re-fitting the headlamp reminds one Yamaha is from the land of sumo - does everybody have the same struggle trying to gently (Ha!) push all those cables inside, snag the rim over the shell and get the screws in? Or am I doing it all wrong?

The newly-ordered bits take total spend since buying the bike to £2,025.29

Hey ho.

 

[peanut]

The newly-ordered bits take total spend since buying the bike to £2,025.29

Hey ho.

ouch ! still... think of all the fun you are going to have when its running well ....priceless

 

[Raymond]

Obviously, there are complications caused by Yamaha in their wisdom changing the carb type fitted to the XS650 - from the caution given on the Yambits site I suspect that the change might have reached different markets at different year models? Typical of me not to be aware of this until too late but it appears I have got away with it as my carb bodies appear to be 78-79.

Got to be patient till new slide comes from Holland. And then, who knows . . .

Onwards and upwards.

Well, the carb slide arrived today and there were a couple of surprises. First was that I thought I was buying one slide, but two arrived. First thought, that's good, I'll replace both.

Second surprise - they are not the right slides. It's the needle retaining arrangement. Difficult to show in a photo. We have established that my bike has the later, 78-79 carb bodies, but the slides I have been sent do not have the well at the bottom to take the spring nor the two holes for the pins on the needle holder hat thing. So the hat won't fit.

Having bought them from Heiden Tuning in Holland, I now face the task of asking them about the types of BS38 slides they have and identifying the correct one. Which I thought I had already done.

Maybe it would be easier to keep the new slides and buy the correct needles and retainers for them?

Are there more than two types of slide for these carbs?

Why is this stuff never easy.?