1981 Yamaha XS650S - Project Bike #5

Mailman · Aug 10, 2020

rbirkey said: ↑

Hello Everyone,

I hope you are all doing well during these weird times. I am doing fine, but have been busy on some other projects. But, I am back working on this project and hoping to get the 81 Yamaha XS650S running in the next week or so as I have a buyer for it!

I am currently working on wiring everything back up and integrating some flexible aftermarket LED turn signals and taillight unit that I purchased from Dime City Cycles. I have integrated them on a 2004 Bonneville, but not yet on the Yamaha. I have the lights (including the necessary resistors) working (they go on) but they do not yet flash on and off.

I bought a new flasher unit from MikesXS, but it has only 2 prongs. My original flasher is a sealed unit with 6 leads - see photo. The Black and Brown leads I recognize being in the turn signal wiring but I don't understand the others.

Any thoughts on either integrating the 2-pole flasher, or where to get the appropriate replacement?

I'm also installing the extra brake line and connectors for the "European" front disc brake setup.

Thanks.

Randy

View attachment 173168
View attachment 173169
Click to expand...

Randy, good to see you back again. Your bike is coming along nicely!

Jim · Aug 10, 2020

rbirkey said: ↑

My original flasher is a sealed unit with 6 leads - see photo.
Click to expand...

That's not the flasher relay, it's the flasher canceling unit. Relay is a round metal can with 3 terminals.

rbirkey · Aug 10, 2020

Thanks - I guess this must be it... it threw me off because it is square and didn't look like the one I replaced on the 1977 Yamaha XS650D. So will the 2 prong unit work with the three prong receptacle, or do I need to get a different unit?

Randy

Jim · Aug 10, 2020

I got the 2 prong to work on my 3 prong 80SG. Honestly don't recall how I wired it, but yeah... it's doable. Iirc I just started plugging the connector in at random angles 'till it worked.

fredintoon · Aug 10, 2020

rbirkey said: ↑

Thanks - I guess this must be it... it threw me off because it is square and didn't look like the one I replaced on the 1977 Yamaha XS650D. So will the 2 prong unit work with the three prong receptacle, or do I need to get a different unit?
Randy
View attachment 173177
View attachment 173178
Click to expand...

Hi Randy,
a 2-prong flasher will plug into the XS650 stock 3-way flasher receptacle TWO ways.
One way, nothing happens. T'other way works the flashers but ain't compatible with the self-canceller.

Paul Sutton · Aug 10, 2020

Looks like it will plug into an Aussie or NZ power socket too. Anyone game to try it? Cannot be worse than a Taipan in your bedroom.

rbirkey · Aug 20, 2020

So, I decided to rebuild the front brake master cylinder while I had everything apart and adding the second front disc. I ordered the 08-0204 kit from MikesXS thinking is was the right one for dual discs - but when I took my master apart, it seems I have the single disc master cylinder (Duh!) which would be kit 08-0219. My question is... will the single disc rebuild be sufficient for my dual disc setup, or do i need to upgrade the entire master cylinder? If so, any recommendations?

rbirkey · Aug 20, 2020

In speaking further with MikesXS I decided to order their 1MH Front Master Cyl. (16mm. bore) - Part 08-0265

Machine · Aug 20, 2020

rbirkey said: ↑

In speaking further with MikesXS I decided to order their 1MH Front Master Cyl. (16mm. bore) - Part 08-0265
Click to expand...

What did you think they would tell you ? Not to buy their parts? Lol
Your stock master cylinder would have been a fine choice to use with the added left disc setup assuming you are using XS style matching single piston calipers.

5twins · Aug 20, 2020

Yes, the stock 14mm MC is actually a bit too big for one disc but it's said it works well with two.

Jim · Aug 20, 2020

I converted mine to dual disk with the single OEM master. Works great. Nice progressive feel and enough power to lock the front tire. Have a read here.

fredintoon · Aug 20, 2020

Jim said: ↑

I converted mine to dual disk with the single OEM master. Works great. Nice progressive feel and enough power to lock the front tire. Have a read here.
View attachment 173772
Click to expand...

Hi Jim,
me too with that same dual disk set up. Did mine 12+ years ago. Front wheel lock on dry pavement if you squeeze hard enough.
As you gotta do when pickups cut in front of you.
Got a theory why some pickup drivers always wear ball caps. It hides the circumcision scar.

Machine · Aug 20, 2020

fyi I let my red hair fly in the wind

fredintoon · Aug 20, 2020

Machine said: ↑

View attachment 173773
fyi I let my red hair fly in the wind
Click to expand...

Hi Machine,
perhaps you should pull up your zipper before you drive? Lest an EMT finds you unconscious after a collision?

Machine · Aug 20, 2020

Lol

KennyD77 · Aug 21, 2020

5twins said: ↑

Yes, you're going to want new mains and pilots, larger sizes than stock, but the needles and needle jets usually don't need replacing. That's a good thing because you can't get genuine ones anymore, only knock-offs. Be aware that these BS34 carbs use different types of mains and pilots than the BS38's you were working on. The mains are the large round style, Mikuni part #N100/604 .....

..... and the pilots are the BS30/96 type .....

One size up on the pilots should be good (#45) but the mains will depend on your mods. One size up (to a #135) might do for only one mod like the pods, but more than that will most likely require more sizes up. If you plan the usual "pods and pipes" modding, I'd skip right over the 135 and get 137.5 and 140.

You haven't quite disassembled everything. I see your pilot circuit air jets are still in the bell mouths. That's OK, they just flow air to the pilot circuit and rarely get dirty or plugged. You can blow through them to insure they're clear with them still in place. But, they are another tuning factor for your idle circuit. You can change them. Usually, you reduce their size by a couple. This lets less air in and makes the idle circuit richer. They don't have as big an effect as changing the pilot jet size so can be considered a "fine" tuning adjustment.

I also see the metal plugs are still in place covering your mix screws. Personally, I feel they need to come out so you can access the mix screws. The tiny o-ring on the mix screw usually needs replacing by now, not to mention the screws are set very lean from the factory. The removal process involves drilling a 1/8" hole into the plug and threading a sheet metal screw into it. Then you grab the screw with vicegrips, twist and pull the plug out. The tricky part is not to drill too deep, not all the way through the plug. The mix screw is just below it and made of soft brass. Drill through and you often damage the screwdriver slot on top of the screw. To further ward off damage to the screw, it's a good idea to grind the sharp point off the sheet metal screw .....

You'll notice a tiny hole in the center of the plug. Use this to judge your hole depth. The plug is about 3/16" to 1/4" thick. Drill a little bit and check the hole. Look at the size of that tiny hole in the center of the plug. Drill a little more and check it again. Keep doing this, drilling just a little at a time, until you see the tiny hole in the center of the plug begin to get larger. Stop drilling any further, you're almost through the plug.
Click to expand...

If you can find 1/8 Left hand drill bits, a lot of times when you start to drill it will grab the plug and spin it right out. My two cents. Hope it works out for you.

rbirkey · Sep 2, 2020

Hey all,

I have rebuilt the stock master cylinder and it feels like it is working as it should. I have installed all new front brake lines and am now trying to fill the new front system with brake fluid and bleed the air. So far, I've spent several hours trying to get the air out and get the system working. No success.

I'm using a compressed air tool that sucks the open bleeder valve, while keeping the master cylinder topped up with fluid. It works great on my Triumph Bonnevilles but so far, no luck on this setup.

I am wondering if the used left front caliper is the issue. The piston is pretty tight, and doesn't want to move very easily. I've had it apart and cleaned the crap all out, and the piston has some pitting around the seal section. Maybe I need to replace the piston and the inner seal?

Any suggestions?

5twins · Sep 2, 2020

What you especially need to clean out is the groove for the square section o-ring "seal". If there's crust built up in it, it will force the "seal" out more and make the piston stick.

Machine · Sep 2, 2020

Been wondering for quite awhile about if using the original caliper hose (hoses) junction in a dual line application, does clearance above the front fender still allow for the forks to be raised in the triple clamps any higher than flush ?

Or can a guy expect a dented front fender on a pot hole hit lol..

rbirkey · Sep 2, 2020

Rechecked the caliper seal ring and slot and it is clean and in good shape. Now I am trying to put everything back together from the bottom up and filling each section with brake fluid as much as I can as I go. Hopefully that will be enough to start getting some pressure so I can bleed it.

Log in or Sign up

1981 Yamaha XS650S - Project Bike #5

Mailman Hardly a Guru Top Contributor

Jim Beyond the edge is the unknown. Here be Dragons XS650.com Supporter Top Contributor

rbirkey TriumphBonneville.org

Jim Beyond the edge is the unknown. Here be Dragons XS650.com Supporter Top Contributor

fredintoon Fred Hill, S'toon. Top Contributor

Paul Sutton Still Looking Good Top Contributor

rbirkey TriumphBonneville.org

rbirkey TriumphBonneville.org

Machine Race the wind Top Contributor

5twins XS650 Guru Top Contributor

Jim Beyond the edge is the unknown. Here be Dragons XS650.com Supporter Top Contributor

fredintoon Fred Hill, S'toon. Top Contributor

Machine Race the wind Top Contributor

fredintoon Fred Hill, S'toon. Top Contributor

Machine Race the wind Top Contributor

KennyD77 77 D Model

rbirkey TriumphBonneville.org

5twins XS650 Guru Top Contributor

Machine Race the wind Top Contributor

rbirkey TriumphBonneville.org

Share This Page

Forums

Log in or Sign up

1981 Yamaha XS650S - Project Bike #5

Mailman Hardly a Guru Top Contributor

Jim Beyond the edge is the unknown. Here be Dragons XS650.com Supporter Top Contributor

rbirkey TriumphBonneville.org

Jim Beyond the edge is the unknown. Here be Dragons XS650.com Supporter Top Contributor

fredintoon Fred Hill, S'toon. Top Contributor

Paul Sutton Still Looking Good Top Contributor

rbirkey TriumphBonneville.org

rbirkey TriumphBonneville.org

Machine Race the wind Top Contributor

5twins XS650 Guru Top Contributor

Jim Beyond the edge is the unknown. Here be Dragons XS650.com Supporter Top Contributor

fredintoon Fred Hill, S'toon. Top Contributor

Machine Race the wind Top Contributor

fredintoon Fred Hill, S'toon. Top Contributor

Machine Race the wind Top Contributor

KennyD77 77 D Model

rbirkey TriumphBonneville.org

5twins XS650 Guru Top Contributor

Machine Race the wind Top Contributor

rbirkey TriumphBonneville.org

Share This Page

Useful Searches