Excalibur Updates

Excaliburs, New Yorks

Excalibur Updates

Postby swtuggle » 22 Nov 2011 15:51

Figured I'd start a fresh thread...
Progress thus far; replaced both clutch seals, and replaced the timing belt.
Yesterday, my new PHBH 28 BS carbs arrived. I dismantled them to confirm jet sizes, and just about every spec I was quoted by the distributor was incorrect.
So below are both carb's factory settings:
60 choke
50 idle
268T atomizer
118 main (I have a pair of spare 115s)
50 slide
X6 needle
9.5g plastic float
200 inlet valve

Unlike the old emission 30ES, these have no float bowl vent ports, nor a vacuum port, so the whole PCV system (tubing, check valves, collector manifold) is excess. I routed the now open-ended rocker cover vent hoses down along the frame, but the crankcase vent pipe is still connected to the black collector manifold under the seat. Will static crankcase "pressure" relief be sufficient or do the crankcase vapors really need to be drawn out?

I'll crank it up on Thursday, adjust the carbs, then check the timing. The way these carbs are set up, does anyone think I'll have any jetting problems?
swtuggle
 
Posts: 47
Joined: 24 Oct 2011 02:36
Location: Steilacoom, Washington, USA

Re: Excalibur Updates

Postby swtuggle » 28 Nov 2011 16:31

Got it started this weekend. Adjusted the mixture and speed screws for a smooth idle around 1100 rpm. However, even hot, it wouldn't restart unless the speed screws were set for a 1300-1400 idle, nature of the beast?
The only problem is cold starting. With either full or partial choke (handlebar-mounted choke lever), it just won't light off. Checked the #1 plug and it's dry. So I assume that means the #60 choke jet is too lean, and fitting the original carb's #50 will cure it, since it started and ran well on choke with the old carbs. My question is...does a higher # choke emulsion tube/jet mean leaner? I haven't pulled the 60s out and compared them to the old 50s to see where the holes sit on each of these tubes.
swtuggle
 
Posts: 47
Joined: 24 Oct 2011 02:36
Location: Steilacoom, Washington, USA

Re: Excalibur Updates

Postby 'It must be a .....' » 28 Nov 2011 23:39

Hi, here are the PHBH 28 BS carb settings for 501 Camels and 501 Coguaru

501 Camel 501 Camel electric start 501 Coguaru
Pilot jet 42 42 55
Main jet 76 76 76
Start jet 50 50 50
Needle X18 X18 X18
Slide 40 40 40
Atomizer ? ? BC 264

Note the settings are taken from the bikes and not a manual.
Both Camels came from France and ran really well (starting, tick over, performance etc) on these settings here in the UK.
The Coguaru came from Spain but I've yet to run the engine.

Very different settings from yours on the same engine.
I hope this is of some use/interest?

Good luck as once set up well they are brilliant bikes.
Take care, Ian
'It must be a .....'
 
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Joined: 12 Sep 2010 12:25

Re: Excalibur Updates

Postby swtuggle » 29 Nov 2011 05:31

Thanks for that info, Ian.

No doubt I may need to tweak the jetting in these replacement carbs.

For example, today I replaced the new carbs' 60 starter jets with the 50s from the original smog carbs. To the naked eye, they appeared identical. Relatively same size orifice in the jet, holes in the same location along the lower portion of the emulsion tube. Yet, once the old 50s were installed, the bike easily roars to life, jumping to 3000+ rpm on full choke. Oddly, the lever has a partial position, but with either set of jets fitted, the bike would not stay running with the lever in the partial position. But then I realized the PHBHs, if not all flip-lever choked Dellortos, only have two positions, full choke or off.

Back to the fine-tuning point, once I get some quality saddle time in (it's been overcast and wet, in the 40s-50s lately), I'll see how the carbs behave throughout the entire rpm range under various load and throttle settings. It's folly to think only the starter jets need tweaking, but after a few short romps in the neighborhood, I've found it runs quite well, so optimum jetting is not too far off. As EVguru had mentioned in another post, the only way to tell if it's optimized would be from dyno runs. I just may try that one of these days.
swtuggle
 
Posts: 47
Joined: 24 Oct 2011 02:36
Location: Steilacoom, Washington, USA

Re: Excalibur Updates

Postby swtuggle » 15 Dec 2011 16:22

After installing 47 pilot (idle) jets, and 115 mains, I took it out for a road test, finding that small and large throttle positions are working well, but approximately 1/4 to 3/4 position causes the engine to stutter, shudder, miss, cut out, etc. Once home, I replaced the X6 needles with X22 with the hope they'll cure that midrange leanness. Also, during that ride, the rear brake started dragging, so I opted to flush and bleed it first before another road test. Many frustrating hours later, it still will not prime and bleed.

I tried a MityVac, but the only way fluid can be drawn through the caliper bleed nipple is to partially pull the piston out of the bore allowing an unobstructed path between the supply and pressure sides of the master cylinder. I have a reseal kit coming from Herdan, but am not entirely confident that will fix it. The spring is strong, and the o-ring and tapered seal (flare towards outlet) show no signs of damage. The only anomoly I can see is the supply elbow rubber grommet on the top of the cylinder shows signs of dry rot cracking, so maybe just enough air is getting in to keep it from being a closed system, however no fluid is escaping through the grommet.

I've seen the threads where others have battled such a simple system as well, but none of those tricks have worked. Very annoying and embarassing.
swtuggle
 
Posts: 47
Joined: 24 Oct 2011 02:36
Location: Steilacoom, Washington, USA

Re: Excalibur Updates

Postby swtuggle » 25 Dec 2011 18:03

Happy Holidays, all.

Just wanted to post my findings regarding my inoperative rear brake for others who may run across this exact dilemma. Hindsight being 20/20, it makes sense why the caliper froze in a partially applied position, then when it slowly depressurized on its own, the brake wouldn't reapply or allow a bleed after I changed the dirty, brown old fluid.

I ordered a master cylinder (MC) reseal kit, thinking that's the only other thing it could be. The package said "500/501 -86," which to me means up through 1986, because the pressure seal and inlet elbow seal supplied were completely wrong, so Morini must have sourced a different Grimeca MC for 1987, the year of my Excalibur.

Regardless, when I pulled the inlet elbow and seal out, there was a lot of sediment in the bottom of the cavity, which had clogged the rearmost (pressure end of piston/cylinder) of the two drilled passages into the MC. Using a .032" piece of safety wire, I was able to eventually dig and poke through into the cylinder, freeing the orifice which supplies the fluid to the pressure chamber in the MC. This may be elementary to those experienced with disc brake systems, because after I finished with the rear, I bled the front brake and noticed the two requisite orifices in the front MC reservoir.

Original seals back in place, and a MityVac bleed performed, it now applies strongly with minimal pedal travel.

Now that I can safely stop again, it's back on the road to see what kind of difference those X22 needles made.
swtuggle
 
Posts: 47
Joined: 24 Oct 2011 02:36
Location: Steilacoom, Washington, USA

Re: Excalibur Updates

Postby swtuggle » 30 Dec 2011 16:48

Had the Ex out the other night (the bike, not the former Mrs.) and with the X22 needles, that lean miss/stutter was nearly banished. Only shows itself when I hold the revs around 5-6K, being a minor stutter. Haven't held it at higher rpm's due to the bellowing racket emanating from my new silencers.

Oh yeah, that's another change I've made. Wanted to shed some weight and gain some V-twin roar, so I bought a pair of cheapo 17" Emgo shorty reverse cones. Besides the noise, I've found by reading the plugs, that the practically-straight-through design has leaned the mixture all throughout the rev range. At idle, the left silencer emits an eye-burning smelly exhaust pulse. All that comes out of the right silencer is a warm puff of air.

Since both pipes are linked via the balance tube mazework under the motor, I'm not so sure it's the forward cylinder that's idling lean, even though that's the one that has the most direct connection to the left silencer. Both plugs (new BP6ES with only 20 minutes of use) look the same so far, having a light gray ground strap and a light gold patina starting on the surface of the thread base (where the strap welds to).

I then pulled the silencers, performed the "crumb cup mod" found all over the internet using one on the forward and one on the rear end of the perforated tube. Additionally, I replaced the minimal stock fiberglass packing with a wrap around the rear 80% of tube with another wrap around the rear half to help completely fill out the megaphone with fiberglass. Will start and ride it later today, so I'll see what that has done for the noise, and just as important, for the jetting.
swtuggle
 
Posts: 47
Joined: 24 Oct 2011 02:36
Location: Steilacoom, Washington, USA

Re: Excalibur Updates

Postby 'It must be a .....' » 15 Jan 2012 16:02

Hi Steve, still having problems with PMs will try again soon,
take care, Ian
'It must be a .....'
 
Posts: 162
Joined: 12 Sep 2010 12:25

Re: Excalibur Updates

Postby swtuggle » 24 Jan 2012 16:15

Still messing with the carbs...
I ordered and received 40 slides, 264T atomizers, #1 needles, 42 & 45 pilots, & 112 mains. Installed all to include the 42s with the needles on the second groove. Tested, and had a serious bog around 1/4 throttle. Installed 45s, same thing. Then 47s, and moved the needles up one groove to the third. Short ride in cold windy rain felt much better, although I wasn't able or foolish enough to hold it wide open in those conditions. However, I'll wait for further tweaking until it warms more. I'm afraid I'm wasting effort right now, because the current setup will be too rich once it's back to normal riding temps, since all of my recent test rides have been between 35-45 deg F.

Different subject, starting researching Morini rear sprockets, and I counted the teeth on mine. 45...no wonder first feels like I'm riding a trials bike, with each upshift barely dropping the revs, and it turns around 6000-6500 rpm in sixth on the highway. So now I'm contemplating obtaining a 38 or 40 tooth sprocket. Haven't checked it yet, but I assume the front sprocket is the standard 14 tooth. With such a change, I know acceleration won't be as rapid, but I'm getting a little tired of the extreme left hand and foot workout, having to row the gearbox continuously in urban areas.
swtuggle
 
Posts: 47
Joined: 24 Oct 2011 02:36
Location: Steilacoom, Washington, USA


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