2013 GU poor fuel economy

Are ya having a problem with your rig? We'll try to help. Share your tech tips and experiences here. Dr. Billy Glaser, author of the "Unofficial 750 Ural Service Manual" site myural.com, is moderating this section.
Forum rules
Here is the place for you to ask questions about or share your experiences about servicing or repairing your Ural or Dnepr. Please post topics concering modifications or accesories in the "Modifications and Acessories" section. Please post oil related questions in the "Oil Threads" section.
User avatar
hillbillybob
Comrade Colonel
Comrade Colonel
Posts: 263
Joined: Mon Sep 21, 2015 7:08 am
Location: Livingston County, New York

Re: 2013 GU poor fuel economy

Post by hillbillybob » Fri May 11, 2018 8:33 am

The easiest way to increase fuel mileage is, to decrease your speed. Run less rpm's in all gears...no need to be spinning 4000 - 5000 regularly. I seldom get above 3250 rpm, 6782.6 km tracked - 100.865 gallons - $309.18 fuel cost - 67.24 kmpg - 41.78 mpg. These numbers are Ural kilometers.....they are 7.5% less than actual kilometers. Actual figures entered at fuelly.com.

I run two windshields, wife and dog at least 70% of the time.
Current Rides:
2006 Ural Troyka "Boris"
2000 BMW R1200C "Schultz"
1999 BMW R1200C "Dooley"
2011 Chinese 150cc Scooter "Johnny" (16,338 breakdown free miles)
Image

User avatar
tparr
Hero of the Soviet Union - 2019
Hero of the Soviet Union - 2019
Posts: 99
Joined: Wed Apr 11, 2018 6:30 pm
Location: Lewisburg, ohio

Re: 2013 GU poor fuel economy

Post by tparr » Sun May 13, 2018 7:54 am

I thought I would update you on my progress. I checked the timing and advance and it was spot on. got the carbs synced, they were off. I still have not checked the valve lash, its on my to do list. Made a few more fixed distance runs and am getting a consistent odometer error of under reporting the mileage by 7.5%. This makes the mpg increase slightly.
The biggest change I made was to re-jet the carbs. Was 40/122 with three shims and now is 42/130 with one shim. I messed up when i installed the diaphragms, turns out i didn't get them on correctly. The engine started fine but had no mid to upper acceleration, acted like it wasn't getting any fuel. It was starving for fuel because there was an induction leak past the goober-ed up diaphragm! So in my trouble shooting I added the shim trying to richen the mixture and then i figured out it was the diaphragm. The engine is running good now and i'm tired of taking the carbs apart so i will leave the shim in for now and monitor the mpg for a few tanks. Now to put some miles behind me. :D
I appreciate all the input. Tim
2013 Gear Up, Forrest Fog
new to me in 2018, 19,995 km

User avatar
LRP
Hero of the Soviet Union - 2019
Hero of the Soviet Union - 2019
Posts: 2483
Joined: Sun Sep 28, 2008 8:25 pm
Location: Deltona, FL

Re: 2013 GU poor fuel economy

Post by LRP » Sun May 13, 2018 8:41 am

I suspect someone has drilled out the main jets. From the dark color of the sparkplug insulator, you are running very rich. Unleaded gas
in the right ratio barely colors the insulator--should be just a tinge of beige.

Ural designed the engine to run on 91 octane or higher. You may get detonation and holed pistons using regular.

A 128 main jet would be a good starting point.

LRP :moto:

Dick
Army Bird Dog Pilot, Nam.
2018 CT
Traded '08 Patrol
2008 Royal Enfield cast iron military
1983 Honda Passport

19 previous motos

User avatar
tparr
Hero of the Soviet Union - 2019
Hero of the Soviet Union - 2019
Posts: 99
Joined: Wed Apr 11, 2018 6:30 pm
Location: Lewisburg, ohio

Re: 2013 GU poor fuel economy

Post by tparr » Sun May 13, 2018 9:35 am

LRP wrote:I suspect someone has drilled out the main jets. From the dark color of the sparkplug insulator, you are running very rich. Unleaded gas
in the right ratio barely colors the insulator--should be just a tinge of beige.

Ural designed the engine to run on 91 octane or higher. You may get detonation and holed pistons using regular.

A 128 main jet would be a good starting point.

LRP :moto:

Dick
After re-jetting the spark plugs look very good, straw color all around the insulator. It is a possibility the old jets were drilled. I'll consider changing back to 91 octane gas. thanks

P.S. i've got a couple L-8 hours in my logbook but no L-19

Tim
2013 Gear Up, Forrest Fog
new to me in 2018, 19,995 km

User avatar
jaybird
Order of Suvarov
Order of Suvarov
Posts: 2764
Joined: Thu Jul 01, 2010 4:41 am
Location: The foothills of the Forked River Mountains, West Barnegat NJ (Do It In The Pines!) 08005

Re: 2013 GU poor fuel economy

Post by jaybird » Sun May 13, 2018 10:02 am

Ural designed the engine to run on 91 octane or higher. You may get detonation and holed pistons using regular
I have over 110k Kilos on '05 Gear Up, most of it on regular gas. I've had a lot of things break and come apart, but never any holed pistons, and no detonation that I'm aware of.
I think the requirement of 91 octane has more to do with emissions than holed pistons. Although I've never been to the FSU, I'd also be surprised if the average Russian was putting "premium" gas in their vehicles.
I'm no gasoline or engine expert, so maybe I'm just lucky, but I do know there are other Ural owners beside me, that run regular gas without any ill effects.
I will add that I'm currently using "premium" gas in my Gear Up as I'm primarily only running it off road and in the snow, so it sits a lot in between rides and I think the "premium" gas keeps better.

Happy trails,
Jaybird
2005 Gear-Up, Mr. Nat_ural 108,000+ Kilometers and counting
2013 Retro, Black beauty, AKA Lucky "13"
1995 Olive Tourist
1975 Enfield Diesel Bullet
2008 Enfield Bullet 500
1974 BMW R 75/6
Etc.

User avatar
windmill
Order of Victory
Order of Victory
Posts: 8088
Joined: Tue Feb 12, 2008 1:17 am
Location: Kent, Wa 98042

Re: 2013 GU poor fuel economy

Post by windmill » Sun May 13, 2018 1:15 pm

LRP wrote:
Ural designed the engine to run on 91 octane or higher. You may get detonation and holed pistons using regular.
A lot depends on ones riding style, environment, and fuel. Some can get away with lower grades, and some can't. I'm not an aggressive rider, my environment is relatively cool, but fuel is high in ethanol content, there's lots of long, steep hills, and significant traffic so I run premium. The main issue I have with regular is run on.
Barry

"Take care, sir," cried Sancho. "Those over there are not giants but windmills".

2007 Patrol 100k km and counting,
2018/20 M70

User avatar
Wildhorse Cafe
Hero of the Soviet Union - 2019
Hero of the Soviet Union - 2019
Posts: 1984
Joined: Mon Sep 08, 2014 5:28 pm
Location: King City, California

Re: 2013 GU poor fuel economy

Post by Wildhorse Cafe » Sun May 13, 2018 1:49 pm

Back to basics. Air pressure, air filter, carb sync, driving profile. I have the same jetting on my '11 and average 200 to 220 depending on my profile.
2011 Patrol, The Higgs Bison Super Collider, formally known as, the Orange and Silver Pumpkin Coach.

2013 Black Retro, Chernaya Krasota, formally known as, my name is nobody.

When you set out on your journey to Ithaca
pray the road is long , full of adventure, full of knowledge
not expecting that Ithaca will offer you riches
Ithaca has given you the beautiful voyage

C.P. Cavafy

User avatar
tparr
Hero of the Soviet Union - 2019
Hero of the Soviet Union - 2019
Posts: 99
Joined: Wed Apr 11, 2018 6:30 pm
Location: Lewisburg, ohio

Re: 2013 GU poor fuel economy

Post by tparr » Tue May 22, 2018 4:16 pm

I have been through three more tanks of gas. No calculation from the first tank due to taking the carbs off three times, 23 mpg on the second and 27 mpg on the third. This was with 130/42 jets, one shim, and riding conservatively. Today I checked the valve lash, removed the shim (no shims now) and freshly lubed splines. Drove for about 45 minutes with no discernible change in power. I have been keeping my eye on the oil level and it doesn't appear to be leaking fuel. I'll put some more miles on and report back. I appreciate all the input.

Tim
2013 Gear Up, Forrest Fog
new to me in 2018, 19,995 km

User avatar
tparr
Hero of the Soviet Union - 2019
Hero of the Soviet Union - 2019
Posts: 99
Joined: Wed Apr 11, 2018 6:30 pm
Location: Lewisburg, ohio

Re: 2013 GU poor fuel economy

Post by tparr » Fri Jun 28, 2019 6:32 pm

tparr wrote:
Tue May 22, 2018 4:16 pm
I have been through three more tanks of gas. No calculation from the first tank due to taking the carbs off three times, 23 mpg on the second and 27 mpg on the third. This was with 130/42 jets, one shim, and riding conservatively. Today I checked the valve lash, removed the shim (no shims now) and freshly lubed splines. Drove for about 45 minutes with no discernible change in power. I have been keeping my eye on the oil level and it doesn't appear to be leaking fuel. I'll put some more miles on and report back. I appreciate all the input.

Tim
Follow-up Report:


13 months and 11,257 km later I would like to report a good improvement in fuel economy. I have not changed the configuration of the rig at all. I currently have 17,557 km on the odometer. At about 12,000 km I could feel the engine "loosen up" and could feel just a hint more power and the fuel mileage increased as well. My last fill up the trip odometer reports 201 km and the tank took 4.1 gallons of petrol. I just drove a fixed distance course to check the accuracy of the trip odometer and it still under reports km by about 6%. So adjusting the indicated km to actual km is 213 km or 132 miles. 132 miles/4.1 gal. = 32 mpg. ( if my math and logic are correct). :D Thanks for listening. Tim
2013 Gear Up, Forrest Fog
new to me in 2018, 19,995 km

User avatar
Lokiboy
Hero of the Soviet Union - 2019
Hero of the Soviet Union - 2019
Posts: 4192
Joined: Fri Apr 29, 2011 9:58 pm

Re: 2013 GU poor fuel economy

Post by Lokiboy » Fri Jun 28, 2019 8:33 pm

Tim... 32mpg is right in the ballpark. I average between 35 mpg in the summer and 32 mpg in the winter. And if I’m hauling camping gear and hwy speeds can go as low as 30 mpg.

Glad it’s improved for you.

As for the type of gas you wanna put in it, that’s totally up to you. I’m with Jaybird and his observations - I run only 87 octane.
2011 Gear Up - "Erika"
Yorktown, VA

Mains: 127, Idle: 40, Needle: 1 shim
MKIII air filter
100,000 km and counting

Post Reply