Jetting an Ural

Sven, it may be time to go introduce yourself to the Soviet Steeds: http://www.sovietsteeds.com/forums/index.php where all things Ural are dis-cussed. We have some good friends over there from our joint gatherings with the TURD's (the Texas Ural Riders Division of the Soviet Steeds).

Lee,
Thank You very much for the suggestion. I did not do so yet because of 2 reasons.
The friendship here in this forum is very good and I see a lot of knowledge that is given sincerely by heart.
I am familiar and feel comfortable with the Forum appearance and personal use we have here in sidecar.com While I felt it pretty cold or impersonal the few times I lurked in other motorcycle forums.

For today I will hit up mountain into the cold clouds to fix some stuff in a saw mill.
A good excuse to test the rig.
Sven

We did the job and had a good time afterwards cruising through the woods and up close to the entrance of the volcano Barva.
What I loved most was the colour of the spark plugs and decent head temperatures in all tested conditions and gas positions. perfect. Perhaps because it is cold these days, but up to 2300 or 2400m = 7500 or 7900 feet Sophie took up speed much better then I did expect Even gas mileage was decent in spite the long turn through the forest and steep hills ...A whole different story compared with the Jawa. I'd say a difference like night and day.
But the badly steep parts the Ural too is suffering, and the bad road I will not enter until I have changed the low mufflers against the high pipe.

The change of the bank against the spring saddle is a great relief and prevents back pain... it is perhaps not a biggy for long hours riding, but great for to ease our bad roads.
🙂 🙂 🙂

Thanks for the update. And the pics!

Sven, here's what seems to be some good general carb tuning/jetting advice posted by KenH at http://www.twtex.com/forums/showthread.php?t=92402 -- more follow-up details can also be found there:

...First, make sure everything else is perfect. Many $$$$ have been wasted on carbs when carbs were not the problem.

See, you really can tune a carb and never look at the sparkplug. All you have to do is let your britches be your guide.

Lee,
thank you very much for the link. The other explainations there were pretty easy to understand too.

Today was a strange day. Beside one Taxi driver I was about to pull out of his cap, as he tried intentionally to hit another car and nearly kicked me into the sidecar (just because, that other driver had blamed the cap's driver's negligence.). Myself I felt like a taxi. I spent a full tank getting downtown in and out the whole day at mostly pretty high speeds and for us low temperatures 16-18°C=61-65°F. And surprise....
I got the lowest gas consumption ever with Sophie Travelair.
8,35l/100km = 28.3 miles/gal
That sounds to me as about the best she can get.
I start to believe that the carbs always had trouble with sincronization and lousy gasoline in USA.
For today in the evening I made one new test, I changed to our regular with 91 Oktan. In case pinging starts again I will go back to Super with 95 Oktan.

The tips given in the link I will print out and follow as I do not like the idea to play so much with the plugs, as the threads might strip earlier or later.

I have a few translation problems. ,What means?
ballpark
to burble
britches

Thanks for all help.
Tomorrow will be a good day for riding, as we will have elections day. Allways somebody has to be transported somewhere and the Ural definetely pulls attention.
(not always nice, like today when somebody called me Hitler at a red light...but in general comments became friendlier the last days)
Best wishes to everybody
Sven

in the ballpark - approximate; reasonably close
to burble - think a sound, something like "gargle" or "bubble"
britches - pants or jeans (breeches)

Do you still have the catalytic converters in the header pipes? If so, you should stick with the stock jetting of #125 main and #38 pilot, air screws set at 2 turns, jet needle on the third height setting. If the cats have been removed, you should upjet to #130 main and #45 pilot with jet needles set at the fourth notch and airscrews at 3 turns. These are how we set up Urals at my shop, but you might have to go a size or two smaller depending on the elevation down there. Keep an eye on the spark plug condition/colour and adjust the setup as necessary.

There is actually a third "jet" in the carb, it's used in the start circuit and is size #65. Don't touch that one, leave it as is. The pilot jet is the small one way up inside the small tube, you'll see it when you remove the float bowl and turn the carb upside down.

Thank You very much Lee and Mike.
Yes I still have the original pipes mounted and hope to keep them for a while until the engine gets realy free.
Yesterday on elections day (with a good positive surprise) I had the oportunity to go the real steep roads with one passenger in my mother in laws neighbourhood at abeout 600m = 2000feet and 28°C 82°F.
I am happy that I have Sophie equiped with the high volume oil pump and powerarc ignition.
There would be no change to go up there on gravel like it was when I explored those roads with my Willies 19 years ago.
Due to the long first gear the only change to get up there and keeping the engine happy is: rev her 4500 to 5000 rpm = 20-23mph 32-37kmh and don't go off the gas.
Downhill pray breaks will last.
I am very amazed how good Sophie behaves. The Jawa would have burnt her heads again. The Ural stayed pretty cool. No racer at all, but she has the charm of a Lanz Bulldog...tractor on a race track (sorry I should better correct: a shock absorber testing track) (with wrong gearing).
Thomas too is surprised as he had his ear for thousands of miles beside the engine.
So whether Super or Regular doesn't matter that much, but NO ETHANOL and sincronized carbs are the clue.
For the jets I will take things calm and go step by step, I cannot be too far off the ideal conditions.
Sven

There is one thing I forgot to mention. Physics: the atmosphere is thicker/taller in the tropics then at the poles. In Europe at 2962 m=9711feet the highest peek of Germany you have trouble to breathe and feel like height sick.
Here there is a road up to 3500m=11475feet to Irazu vukan just 14km = 9 miles sight line out of my office window, My old diesel Renault before the engine repair was till now the only vehicle that went on strike up there. Breathing no trouble, including the Jawa rig felt well there.

For now I better hurry to my shop to double check some trouble due to 50-60Hz migration. The collegue is somewhere in the north in the middle of nowhere in Guanacaste stuck.
Sven

Saturday morning temperature once more raised to normal summer temperatures. After dropping off my son Thomas at his lessons I used the main high way leaving San Jose to Guapiles once and again for to test the main jet size and opening of the air filter. Definitely the air filter is restricting decent maximum air flow, but I do not think about to ride without filter in this country, I prefer to lower the throttle.
The main jet is now only 130, means only one step up from original setting. Pilot 35 and air screw 2 1/2 turn. (sincronizing with vaccuum gage I gave up as I noticed a leak in my switch valve. Now I just eye ball the hole positions and finger test the cable gap. Anyhow the flexible cables seem to be a kind of casuality generator )

In the afternoon we (my wife, son and I)started a serious round trip of 550km 340mi in 1 1/2 days. 1200m 4000ft - 1m 3ft 360m 1200ft - 3300m 11.000ft (top of panamerican highway in 44km 28miles from bottom at 360m) - back home 1200m 4000ft.
Several records we broke: 220km in T-shirt. result = 2 crabs and 1 chocolate... I guess before my longest ride in T-shirt ever was 15km in 32years.
gasoline consume 204km until reserve 7,82 l/100km = 30,2 mpg
Ride 160km 100mi from San Isidro General 360m 1200ft over the Cerro de la Muerte 3300m 11-000ft in 44km 28 mi later to home in 4 1/2 hours.
5 stops on the climb as we got caught behind 2 trailers AND LOUSY FOG. Often I couldn't even see the grass. (well sometimes there wasn't any only a DEEP drop.)
:O :O
Some people want to appear rude with tatoos, raped heads or whatever. In my family we use to say: "Its better to be then appear"
So Thomas and I had under our riding Tourmaster jacket only a T-shirt, jeans and summer gloves without scarf as protection. My wife not even gloves.
"Bless what makes you harder"
On the top we had 0°C 32°F
Timing was perfect. we had ridden in the dark quite a while with "engine saving" fog when at the highest peak we could catch a last glow of sunset before the worst fog trapped us again.

Resumee: I will have to tweak now still a little with idle settings, but the main jets will stay as they are. The head temperatures were always decent 125-174°C (on the highest part still 97°C 207°F), no popping, no pinging no blue mufflers and good gas mileage. All it needs to get the fabulous gas mileages is GET OUT OF TOWN

The photos got a little mixed up_
Terraba river I always compare with the Mosel in the tropics 60km one better view after the other.
Straight, straight straight...I remember this road as a dusty lung and back breaking wash board track crowded with trailers for over 90km until few years ago.
Manuel Antonio beach in Quepos the Mecca of the sunny boys
This is what I would call a big frog. It is by the way the kind that breeds in my farm.
The last glimse at 0°C 32° F on the top of Panamerican Highway 3300m 11.000ft
Sven