Robert Dell Aquila
Shine it on
Read somewhere that my butterfly valves could have too much of a gap, so I have been trying to adjust them. The problem is no initial start with the carbs (have to use starter fluid). High RPM's
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Cam chain timing?
- Thread starter Robert Dell Aquila
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- advance unit cam chain pamco timing
Next up slide drop test. cover port at top of intake bell with thumb lift slide and let drop it should fall slowly and both sides should drop at about the same speed.
If one fails first check your choke valves, a closed choke seals the chamber above the diaphragm so it can be lifted by intake vacuum. then look ovber that diaphragm carefully.
OK a bit of bad news; dipping carb bodies in cleaner with the throttle shafts installed is not a good thing. The shafts that hold the butterflies are sealed to the carb body with rubber "grommets", they don't like harsh chemicals. It's my policy to replace the throttle shaft seals whenever I open up a set of original carbs, 40 year old rubber seldom has the flexibility it needs to make a good seal. It is a rather tricky thing to remove the butterflies the screws are in there pretty tight and staked. The BS38's are harder to do the staking on BS34's is easier to overcome or remove with a file cause the throttle shafts have flats at the butterflies.
If one fails first check your choke valves, a closed choke seals the chamber above the diaphragm so it can be lifted by intake vacuum. then look ovber that diaphragm carefully.
OK a bit of bad news; dipping carb bodies in cleaner with the throttle shafts installed is not a good thing. The shafts that hold the butterflies are sealed to the carb body with rubber "grommets", they don't like harsh chemicals. It's my policy to replace the throttle shaft seals whenever I open up a set of original carbs, 40 year old rubber seldom has the flexibility it needs to make a good seal. It is a rather tricky thing to remove the butterflies the screws are in there pretty tight and staked. The BS38's are harder to do the staking on BS34's is easier to overcome or remove with a file cause the throttle shafts have flats at the butterflies.
Robert Dell Aquila
Shine it on
Ok, I have done the slide test before and timed both for 15 seconds. One of the carbs slides down faster than the other so I will take a look at the choke valves and seals. When I dipped my carb bodies I removed everything. I took off the butterflies and the shafts with the grommets (assuming we are talking about the same thing). It was a bare carb body when I dipped it. Also what do you mean by "stacking"?
Well good on you, you've done good! Staking; deforming the end of the screws so they can't back out.
Robert Dell Aquila
Shine it on
Oh I got you. There is definitely a lot of play in the butterfly rod which moves the valves left to right. I don't want to bore you with carb stuff. There is plenty of information on this forum about carbs. I will go through the "XS650 Carb guide" and report back when I have gone through all the checks. Thanks for all the help. I'll report back soon!
Just to answer your previous question.
Rotating 277° CCW would put you at right cyl TDC, ignition phase.
Rotating 83° CW (backwards) would put you at right cyl TDC, overlap phase.
Rotating 277° CCW would put you at right cyl TDC, ignition phase.
Rotating 83° CW (backwards) would put you at right cyl TDC, overlap phase.
Robert Dell Aquila
Shine it on
So I just went through my carbs and cleaned choke shaft and switched the slides to ones that fall at the same rate. Leaned the needle slot to stock 3rd slot and went up a size on the pilot jets to 30.Bike started right up with the choke on (Rpm's seemed a little higher). Bike ran really well for 10 minutesI shut it off to talk to my neighbor and it started right back up. Only thing is I had to use the electric start, when I kick it, it kicksback way too much (could be timing). I pulled the plugs to inspect and they look pretty good. Results after 10 minutes running.
Looks much better than pic I saw a couple hours ago! Yeah kickback can be a sign of over advanced timing, sticky advance rod or weak advance springs.
Robert Dell Aquila
Shine it on
I'll try and get the timing down. I believe with a pamco all you have to do is turn the plate CW or CCW to advance or retard. I think the white smoke may have been oil burning off because its not smoking anymore. Nevertheless thanks for all the help to you and everyone on this forum. Moving on to my next problem of overcharging my battery. I heard a lot of negative things about my electrosports reg/rec on this forum. Any suggestions for a good reg/rec?
The DIY are prolly the best combo of price n function, but I just use working stock parts, ( I have the parts bins
) A fairly common cause of oil burning on start up is a cracked (or,hard worn) valve seal. Oil seeps in while bike is sitting. 
A popular forum etiquette thing is to put your year, model, basic mods in your signature, helps us answer bike specific questions without having to go back through your old postings to figure out what the heck you're running.....
) A fairly common cause of oil burning on start up is a cracked (or,hard worn) valve seal. Oil seeps in while bike is sitting. A popular forum etiquette thing is to put your year, model, basic mods in your signature, helps us answer bike specific questions without having to go back through your old postings to figure out what the heck you're running.....
Robert Dell Aquila
Shine it on
I was reading about the DIY reg/rec. Seems like a good route. I'll give it a go. Thanks for looking out, I'll edit my signature with my bike info.The DIY are prolly the best combo of price n function, but I just use working stock parts, ( I have the parts bins
A popular forum etiquette thing is to put your year, model, basic mods in your signature, helps us answer bike specific questions without having to go back through your old postings to figure out what the heck you're running.....
lidirtrider
XS650 Addict
I know this is an old thread, but did you ever get this sorted out? I got the same thiing going on.
Robert Dell Aquila
Shine it on
Im pretty sure all of my problems lie within the carbs. My cam chain timing was fine. I believe we go through how to check if its correct in this thread. As of now my bike has a massive air leak on the left choke housing of my carb, and I'm pretty much over trying to get it running right. Trying to sell it actually.
lidirtrider
XS650 Addict
I thought I saw it on Craigslist a little ways back.
