Winter project: upgrading time! (R6 forks and more...)

Another tested added to the ridiculous list:

Unplugged the R/R,. revving the engine high and checking with timing light: does not misfire over 4k
 
In the XS1 Yamaha did not provide a ground path to the fork, headlight, relying on the steering bearings as the ground path, OOPS!
Edit 8-14-22 the XS1 does have a frame to headlight bucket ground wire/harness but the ground wires are not shown in the early wiring digrams.
 
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I have uploaded the following layer of circuitry I designed for my Virago. It shows how diodes can be used to prevent unwanted feedback. Starting with the Key Switch in the Park Position we see the front Park Light is powered on. Also the power flows via a diode to the Tail Light. If the second diode were not in place then power would also be routed back to the Main Head Light and the Instrument Lights - Not what we want!

Also, when the bike is running, switching on the On/Off Light switch activates the relay to send power to the Head Lights and tail lights. If it were not for the diodes power would feed back to the Park Light. In this case it is not a major issue except the Park Light is a filament bulb and does not have the life in it to be run constantly so I'd be forever changing it or replace it with an LED.

Circuit.JPG


The value of the diode needs to be matched to its load. Tail Lights are low wattage so I used 3A diodes. When you find the reason for the feed back you are experiencing it maybe easily fixed by adding a diode or changing the wiring.
 
Older Cessna's had a problem with the alternator causing static (elec noise) over the radios. Their fix was a filter capacitor. You testing shows pretty definitively that it's your alternator putting out the "noise." Any electrical engineers hereabouts that can calculate what size and type of capacitor to use?


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I think I still have an old Cessna maintenance manual around here somewhere. If I can dig it out, I'll see what kind of info it can provide.
 
I have uploaded the following layer of circuitry I designed for my Virago. It shows how diodes can be used to prevent unwanted feedback. Starting with the Key Switch in the Park Position we see the front Park Light is powered on. Also the power flows via a diode to the Tail Light. If the second diode were not in place then power would also be routed back to the Main Head Light and the Instrument Lights - Not what we want!

Also, when the bike is running, switching on the On/Off Light switch activates the relay to send power to the Head Lights and tail lights. If it were not for the diodes power would feed back to the Park Light. In this case it is not a major issue except the Park Light is a filament bulb and does not have the life in it to be run constantly so I'd be forever changing it or replace it with an LED.

View attachment 193161

The value of the diode needs to be matched to its load. Tail Lights are low wattage so I used 3A diodes. When you find the reason for the feed back you are experiencing it maybe easily fixed by adding a diode or changing the wiring.
So originally I planned on using a relay for the headlights too. However after some investigation of the domino handlebar switch and a discussion with a friend we decided not to. Why? The handlebars switch is designed to handle the continues current of everything it's supplies. Secondly I looked at the wiring diagram of my other bike (Yamaha MT07) and even though they use a relay for the headlight l. It's controlled by the ECU but the power still flows through the handlebar switch. And 3rd, since we did not see anything benefits it would take more wires running back an forth.

In addition the domino switch as a separate output wire for parking lights, I use this to only feed the taillight.

The rest I wired according to my diagram. Maybe I need to try to put a diode in the low beam power wire? I just can't figure out how the current is getting to that HI indicator light with just the lo beam on.

But I feel like this problem is less important than the running problems.

I did some more tests today:

Red a lot about grounding systems, hard to understand but here they explain how a star earthing is used wherever possible.

https://www.hpacademy.com/previous-webinars/230-star-point-earthing-explained/

So I rerouted some of my wires for testing this. I'm putting the star or central ground on the old coil lug above the engine. It's bare metal. The grounds from the headlight and other stuff were already going there. Then I routed the R/R ground there. Mounted a ground strap on it from the engine. Ran the battery there and the ignition.

Result. #1: can't rev is over 3-4k and starts misfiring.

Next I removed the ignition ground from the central point and put that straight on the battery. As some people have suggested.

Result #2: no change.

IMG_20210612_173119933_HDR.jpg


IMG_20210612_172750665_HDR.jpg

Everythings on this central ground during result #1
 
Older Cessna's had a problem with the alternator causing static (elec noise) over the radios. Their fix was a filter capacitor. You testing shows pretty definitively that it's your alternator putting out the "noise." Any electrical engineers hereabouts that can calculate what size and type of capacitor to use?


View attachment 193164

If you find this electrical engineer that has hands-on experience working with cars/motorcycles, ask him about a holiday in the Netherlands! I'll hire him for some "holiday-work" on the XS. Because I'm pretty close to giving up
 
If you do a google search for "alternator noise filter capacitor", there's lots of info out there and a lot of commercially available products relatively cheap. Might be worth trying one.
 
A thought on the headlight indicator light...make sure the headlight is wired correctly.. you could reverse the negative/positive and the low/high-beam would still work...but the indicator would also be on.
 
A thought on the headlight indicator light...make sure the headlight is wired correctly.. you could reverse the negative/positive and the low/high-beam would still work...but the indicator would also be on.
Not sure I follow. The indicators and headlight are each on their own power circuit.
 
Yep...so if you have "+" from switch going to the "-" on the headlight; and the "-" going to "+" on the headlight, the light would work but the indicator on the gauge would also be on. It's a long shot...but might be worth checking.
 
So I started a new job and my free time is somewhat reduced. In the last weeks I have done some testing and found out new things. I'm still not there yet and hope really hope to get the bike running asap. Its really annoying that summer is moving along and I cannot seem to find what is wrong with the bike.

A quick recap of what me and a buddy tested on the bike:

No major modifications were done to the bike since the last time. I did go back to wire according to my original diagram, and tested mainly with the Carmo ignition. We tested a bunch with the timing light. Paying more attention to this than before. We noticed the timing light would flash double on one cylinder. And we would see occasional break ups in the flashes on both cylinders. The RHS cylinder would not run smooth (some popping in the exhaust and felt way colder than the LHS).

We flipped the spark plug leads and the speed of flashes would change with this. however the RHS would still be cold and and show intermittent flashing. At this point the focus shifted for electrically to fuel related.

At this point I double checked the base settings of the bike to make sure this was not chasing my tail. Cam chain was on the loose side, fixed that. The valves were sort of ok but I reset them perfectly. I checked for compression: left & right around 138psi. I checked the float height with a clear tube: pretty equal and just under the top of the bowl. I removed the carbs to clean, did not find and clear debris or whatever. Did see that the RHS butterfly was almost shut. So by eye a made it equal to the LHS. I fitted new intake rubbers because one of the vacuum barbs came out while trying to synchronize with a manometer.

At this point the bike ran way, and I mean way smoother at idle!! I'm feeling like the sync was way off and maybe causing this.

Next I did a sync with the manometer tube. By eye I wasn't that far of. Next I did a few testrides, they went pretty good! I rode for max 1h and noticed the bike runs best when cold. Could run it all the way up to 7,5k without to much effort. After fully warming up it would start to pop in the exhaust on the left at idle. And it would kinda sputter if I came to a near standstill and wanted to accelerate.

Next step was setting the Mix screws. I have red the carb guide at least a dozen of times by now, but i have never had real luck with setting them properly. I wanted to do the dead cylinder method to set them. This is where I am now and running into the following. Both mix screws are at 3 turns open (btw i have stock CV34 carbs). I want to have the bike run on one cylinder. I cannot run the bike on one cylinder with the R/R hooked up. So for testing I would just unhook it. I can run the bike on the RHS cylinder only without to much effort. But I cant run it on the LHS cylinder only.... even raising the idle with the butterfly stop screw. So I figured maybe my pilot jet setting is wrong? Instead of messing with the hard to reach pilot jets I tried some different air jets. Going smaller from 127,5 to 118 would make the bike also run on just the left cylinder. So i changed them both to 118 making the setting richer. Trying to set the mix screws with that, I came to 3,25 tuns and 3,5 turns for the other. But I have to say I find this method kinda hard. because I dont really notice a lot of change turning the mix screws.

Did a mini testrun with the R/R still unhooked. Ran OK-ish. Feels similar to the bigger air jets. Still pops in the exhaust on the left cylinder at idle. but if I let it run on just that left cylinder, it doesn't pop:umm:. Finally, hooking up the R/R again the bike runs rough at idle.

So to recap: I don't know if i still have an electrical issue. The bike seems to charge perfectly, only with this last test it seems that the R/R plugged in or out makes a difference. And i was able to run it from 1k to 7,5k. I do think i have to work on the fuelling of the bike. I find it weird that before the sync the right cylinder would pop in the exhaust and now after setting the sync its the left.

what do you guys think? (is this long post even understandable?:eek:)
 
Older Cessna's had a problem with the alternator causing static (elec noise) over the radios. Their fix was a filter capacitor. You testing shows pretty definitively that it's your alternator putting out the "noise." Any electrical engineers hereabouts that can calculate what size and type of capacitor to use?


View attachment 193164
IIRC, suppresion diodes like that were commonly in the 4.5 to 5uF range.
 
Thanks grimly, I will look into that!

Today I went back to the original carb settings, mix screw settings and Yamaha TCI box (which I just got fixed).

It starts up decent. And I was able to ride it for an afternoon. That's the good bit! Some observations:

During some test runs after warming up the bike, I could not rev/ride it over 6k. A few minutes later after a sort stop (got pulled over by the police lol) I was able to rev/ride it up to 7,5k.

Back home I checked the advance of my repaired TCI. That's seems to be ok. However I noticed that the left cilinder occasionally misses a spark and stops flashing the light over 3k. It just totally disappears. Got the lead hooked up correctly.

Checking on the right the light flashes double!! And keeps flashing up to 6k when the bike brakes up.

Repeated this test with the carmo ignition: funny enough it starts and idles fine (unlike last week). It is showing the exact same flashing behaviour as the original TCI. With the only exception that it revs clearly to 7,5k...

Can anyone shine some light (pun intended lol) on this?
 
Btw I'm still looking into theories behind grounding. One question I can't find the answer to is: where was the original factory central ground point on the XS?

I can't find any pictures of this. If anyone could shoot me a picture, would be greatly appreciated!

I have not read it all and perhaps this is over
But one Ground connection goes from
2 o clock hex head bolt on the picture to minus on battery
Other ground points on the bike is connected to the frame metal ..so I don't think there is a Central
Ground Point in the real sense
That design was a Pre Controller design And another type of electronics if any.

I do think a central Ground point is a way to get problems with today's electronic
Given then non existent EMC protection on the original wiring setup.
A central point can transfer spikes according to literature
Between subsystems ..



Ground.jpg
 
made a new sidestand of chromoly tube
sidestand (1).jpg
....its lighter


sidestand (2).jpg


no major modifications to the bike this winter. Planning to build a new shed, that takes all the energy. One thing im working on to get the bike ready for the next season is to de-carbon the engine. I saw lots of build up through the sparkplug holes. Might explain the 'pinging' i believed i heard last fall. In order to work on the engine im making this:
engine stand v1.JPG


should be able to bolt it to the bench and rotate it.
 
made a new sidestand of chromoly tubeView attachment 207033....its lighter


View attachment 207032

no major modifications to the bike this winter. Planning to build a new shed, that takes all the energy. One thing im working on to get the bike ready for the next season is to de-carbon the engine. I saw lots of build up through the sparkplug holes. Might explain the 'pinging' i believed i heard last fall. In order to work on the engine im making this:
View attachment 207034

should be able to bolt it to the bench and rotate it.
This is an engine stand for my beetle engine. It’s meant to bolt onto a work bench but I made this 90 degree bracket that bolts onto a conventional engine stand. Works well.

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D0C55828-48FD-4F7F-9929-347337CFFC84.jpeg
 
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Since I enjoy reading about all the XS650 modifications as much as the next guy, I plan on sharing some of my winter upgrade-stories here.

The list is long, but I want to start with the '00 R6 fork conversion. I have been running a Ducati rotor with calliper set-up for almost ten years now, and i'm ready for a next step. I red some people installed the R6 forks successfully, I like the look of the conventional forks and decided to go for it.

this is what the bike looked like this season
View attachment 156841

last summer I picked up these 2000 Yamaha R6 front forks:
View attachment 156843

Right now i'm trying to understand what needs to be done. It seems like there are quite a lot of variables to take into consideration (triple clamp offset, trail, fork length , steering stem dimensions, bearings you name it).

I've measured the offset difference and the original XS triple clamps are 47mm offset, and the R6 are 40mm. The R6 forks are also about 15mm shorter so i'm guessing the trail is not changing a whole lot since the two seem to counter each other (guestimate hehe). The plan is to reuse the lower R6 triple clamp and machine a new top clamp.

To be continued...
COGNITO MOTO HAVE ALL YOU NEED: https://cognitomoto.com/collections/triple-clamps_handlebars_controls
 
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