1978 XS650 Special Project

Well, normally, the type A (ground switching) Fiat regulator we use isn't for the '79 and older models. However, you can make it work if you rewire the brushes.

VR794.jpg
 
Ads, couldn't find the invoice, the supplier must not have sent a paper copy, but it's this one: https://www.ebay.co.uk/itm/273616060566

and it might be worth taking a look into the annals (!) of Miss November's shady past, where I was given invaluable assistance by @Paul Sutton and @5twins - read this https://www.xs650.com/threads/miss-november-xs2-tribute.55057/post-641793 and some following posts for a discussion of Type A and B regulators and how to wire the unit. The Orange Peril had an engine and alternator swap.

The Fiat regulator is small, light, not very expensive and has done the job faultlessly since.
 
Ads, couldn't find the invoice, the supplier must not have sent a paper copy, but it's this one: https://www.ebay.co.uk/itm/273616060566

and it might be worth taking a look into the annals (!) of Miss November's shady past, where I was given invaluable assistance by @Paul Sutton and @5twins - read this https://www.xs650.com/threads/miss-november-xs2-tribute.55057/post-641793 and some following posts for a discussion of Type A and B regulators and how to wire the unit. The Orange Peril had an engine and alternator swap.

The Fiat regulator is small, light, not very expensive and has done the job faultlessly since.
Great, Thank you for the leads Raymond
Ads.
 
Got tire in and rode 3 miles in the neighborhood
I did have a problem where I left the bike idling for 5-10 mins before leaving and adding air. Bike shut off suddenly. Then on my ride one cylinder cut out. I was a bit low on fuel and when I stopped I did see some air bubbles. Not sure if that was it or something else. I’m still using plugs bike came with so I will start with the plugs. They Havel BP7ES plugs. Same as my 4 cyl XJ650
 
Yes, that's the normal plug but it's getting hard to find because it was discontinued. All that's readily available now is the resistor version, the BPR7ES. If you go with that, you'll want to get rid of the resistor plug caps and just use non-resistor ones. You only want one instance of resistance in each spark plug line. That can be the plug, the cap, or the wire, but you don't want a combination of more than one.
 
I used a spare used BP7ES I had from the '83 XJ650 and the bike seemed to run better. Just holding at 3000rpm on the old plug it was a bit erratic.
replacement plugs it was stable. But the new front tire has something wrong, its not seated in the rim right. Took back to Cycle gear today.
I also realized I did not sync the 2 carbs. Right one was too high. All synced up now. Waiting again :(
Replacement seat came in and already starting to look better


IMG_7442.jpg
 
Yes, that's the normal plug but it's getting hard to find because it was discontinued. All that's readily available now is the resistor version, the BPR7ES. If you go with that, you'll want to get rid of the resistor plug caps and just use non-resistor ones. You only want one instance of resistance in each spark plug line. That can be the plug, the cap, or the wire, but you don't want a combination of more than one.
Shit... Where is the plug cap thread???
 
Yes, that's the normal plug but it's getting hard to find because it was discontinued. All that's readily available now is the resistor version, the BPR7ES. If you go with that, you'll want to get rid of the resistor plug caps and just use non-resistor ones. You only want one instance of resistance in each spark plug line. That can be the plug, the cap, or the wire, but you don't want a combination of more than one.

Good question Kevin. All it takes is for someone to be interested and engaged enough to make a thread. Not hard to do a search and there will be all the info needed on the first page. If you make one up i will link the thread to the the info sticky i made
No... there is a plug cap thread easily found in search I was just realizing my idiocy. (I have a lot of that) My '77 has an after market ignition that call for BPR& plugs and I have been using those on my 81 Red Bike with a stock Yamaha ignition. The "shit" comment begs the question that I wonder how many false signals I may have followed chasing jetting on the VMs and how I could miss such a simple wrong step.
 
I have some new caps on order.
Got my tire back and rode bike in neighborhood for 5 miles. Sure feels like its lean but shut off engine and coasted to garage and will check plugs later.
My idle at the start was about 1100rpm but rose to 2000rpm by the middle of the ride. Will have to investigate that.
My '83 XJ650 is Electronic ignition so this is my first bike with points. Going to check the timing/dwell/gap tomorrow or thursday.
I'm not that happy with my filter setup. Seems the filters I got were bigger than my air box so I crushed the ends to get them to fit and did not put the end covers on. Wondering my make shift filters are making bike lean.
 
A low restriction filter may cause you to go lean. Lean mix can be tuff to get to idle well. Set idle speed at 1200 rpm when the engine is warmed up. Search the Carb section here https://www.xs650.com/pages/tech/ Often a slight intake or exhaust modification can be maximized with a rejetting of the carbs. Changing jets may seem a daunting task but is really quite simple. Most rejetting can happen without removing the carbs from the bike.
 
Tick-over speed will rise as the bike warms up. 2000 sounds a bit high though. As Kevin says, set it when the engine is well hot, should just be a matter of adjusting the throttle stop screw, if not you might need to look at jets.

But with mine set correct for a hot engine, it won't reliably idle at the first couple of junctions so need to hold a tiny smidgeon of throttle for the first mile or two.
 
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