Looking for advice

The "points and condenser system" may not have anything to do with the reason the bike won't run. Clean and adjust the points, get the bike to run and THEN change out the system if you'd like. Don't fret the slightly low compression, it may get better as the engine runs and oil gets circulated throughout. Personally, I think you can do better than stuff from Mikes.

 

77 XS650 is a very cool bike the way it was originally. I'd attempt to keep it close to original.

 

We need more info than 34mm. There are lots of 34mm carbs out there. Pics would be really helpful

 

Those are BS 34's Used on 80- XS's. 81- have a drain screw on the float bowls. Good carbs.

 

The BS34 carbs you were supplied with are better than the BS38's that came on the bike. Those are the carbs the Yamaha switched to in 1980 so they are perfectly suitable for the bike. You will need the corresponding BS34 intakes to bolt to the head though. With few exceptions aftermarket ignitions tend to very expensive and not as robust as the OEM systems. If It were my bike I would keep the points, others will vehemently tell you that you "the ignitions and charging system are the weak link on these bikes" despite the fact that they have worked perfectly for 40-50 years. Points/condensers are cheap and robust. A very quick search of this forum will produce weekly posts all to the effect of "aftermarket ignition, bike wont run, please help!" many tend to be very long threads that result in the purchase of yet another aftermarket ignition because the first one didn't work. The ones that do work often exceed the initial cost of the bike.

 

If everyone replaces their contact breaker systems, the dark art of setting them up will be lost forever.
Almost makes me want to reinstall points on my bike.

 

Yeah, I'm not trying to say that OEM systems are ALWAYS better than aftermarket, I'm just saying the cost:benefit of aftermarket is not always favorable.

 

OEM is a condenser "pack." it's 2 condensers soldered together back to back. Condenser grounds itself... two wires, one to each ignition side.

 

I think the boots can come from
http://jbmindustries.com/
Though I have no personal experience with them. One way or the other, get the bike connected to a 12V power source, have good fuel flow and kick the livin' daylights out of it.

 

Those condenser packs are getting hard to find/expensive, Common motor makes a little bracket to use two individual auto condensers like this but I've found that just mounting two individual condensers (as long as the little bracket is sufficiently grounded) works just fine.
https://www.common-motor.com/honda-motorcycle-gemini-ignition-condenser

 

Pays to post pics. Sometimes a description is confusing..........very, very seldom will you find the XS650 condenser pac has been broken up. They look to be one condenser with one wire that divides into to pigtails.





Best way to determine the difference between BS34 carbs and the BS38's is the caps. 38's have alloy tops and 34's have chrome.

 

My advice is to get a shop manual. They can be downloaded and printed for free (sorry, I don't have the linky - but someone will).

Setting the ignition points is a simple step-by-step process requiring a couple of simple tools and a bit of patience - but it is NOT that complicated nor does it need to be repeated very often. The process is well-explained in most manuals and the bike will run great once you do that job - and get the carbs sorted out.

Compression of 120 psi / side is very good and as was pointed out above, it will likely improve with use.

...oh, and welcome to XS650.com from Canada's sunny southern coast in Windsor, Ontario!

Pete

...just one request - don't cut the bike up until you have ridden it. An XS650 Standard (like yours) is becoming a bit rare and they are absolutely one of the nicest bikes to ride - in stock form.