200cc consumes absurd amounts of gas

Rozkrwawiacz · 08-17-2019, 02:11 PM

Hi. I own 2006 Skyteam ST200. It's a Chinese dual-sport with 163FML OHC engine.
My biggest problem with it is it's thirst for petrol. It's average is about 55 mpg.

I am no newbie when it comes to china motorcycles, so I checked all obvious reasons (like losing gasoline from tank, low tire pressure, and bad tuning) also replaced carb (pz30) and spark plugs and cables,
but here I'm helpless

From now on I will ignore post regarding fuel economy expectations since they're essentially OFFTOPIC.
If you don't want to help solve the problem, because you don't brlieve that there's a problem that's fine, just don't post in this thread, please.

OneLeggedRider · 08-17-2019, 04:26 PM

Ehh, that's about what my Hawk gets.

Red Hawk · 08-17-2019, 06:22 PM

About the same here up & down hills.

Wild Dog · 08-17-2019, 06:50 PM

Absurd?? That's just slighlty higher than avg.
Mine consumes about 70 mpg, so your is not that much, maybe you are just a bit too rich.

Rozkrwawiacz · 08-17-2019, 07:59 PM

@Wild Dog Yeah, I would love 70mpg.
It seems to be avg. for 250cc AFAIK

It is about 25%. Just slightly rich shouldn't cause that much of increase.
And I'm not running rich. In fact I was actually running dangerously lean for some time but it did not seemed to affect mpg.

@Red Hawk I get it on pavement, between towns. (actually town or out of town results are similar)

@OneLeggedRider Isn't Hawk a 250cc?

Wild Dog · 08-17-2019, 08:25 PM

Quote:

Originally Posted by Rozkrwawiacz

@Wild Dog Yeah, I would love 70mpg.
It seems to be avg. for 250cc AFAIK

It is about 25%. Just slightly rich shouldn't cause that much of increase.
And I'm not running rich. In fact I was actually running dangerously lean for some time but it did not seemed to affect mpg.

@Red Hawk I get it on pavement, between towns. (actually town or out of town results are similar)

@OneLeggedRider Isn't Hawk a 250cc?

Hawk is labeled as 250 but is actually 229cc, so not really much bigger than the 200 variant.

I had about 55 mpg when i was running quite rich, after a fine tuning. I'm getting the 70 mpg. My spark plug look right and the bike responds quite well.

paulsstag · 08-17-2019, 08:26 PM

Quote:

Originally Posted by Rozkrwawiacz

Hi. I own 2006 Skyteam ST200. It's a Chinese dual-sport with 163FML OHC engine.
My biggest problem with it is it's thirst for petrol. It's average is about 55 mpg.

I am no newbie when it comes to china motorcycles, so I checked all obvious reasons (like losing gasoline from tank, low tire pressure, and bad tuning) also replaced carb (pz30) and spark plugs and cables,
but here I'm helpless

You mention your fuel as petrol ? and not how americans call it which is gas or gasoline?. you mention miles per gallon and not litres per 100km ? So if you are in England ? then the gallon there is an imperial gallon or 4.5 litres and in the USA a gallon of fuel is not quite 3.8 litres

If you are getting 55mpg out of an imperial gallon of fuel then it's about 46mpg in US terms which does seem like alot for such a small engine?

We need more details please

paulsstag · 08-17-2019, 09:08 PM

Quote:

Originally Posted by Rozkrwawiacz

Hi. I own 2006 Skyteam ST200. It's a Chinese dual-sport with 163FML OHC engine.
My biggest problem with it is it's thirst for petrol. It's average is about 55 mpg.

I am no newbie when it comes to china motorcycles, so I checked all obvious reasons (like losing gasoline from tank, low tire pressure, and bad tuning) also replaced carb (pz30) and spark plugs and cables,
but here I'm helpless

You mention your fuel as petrol ? and not how americans call it which is gas or gasoline?. you mention miles per gallon and not litres per 100km ? So if you are in England ? then the gallon there is an imperial gallon or 4.5 litres and in the USA a gallon of fuel is not quite 3.8 litres

If you are getting 55mpg out of an imperial gallon of fuel then it's about 46mpg in US terms which does seem like alot for such a small engine?

We need more details please

Rozkrwawiacz · 08-18-2019, 05:02 AM

@paulsstag
Well, you got me. I think in l/100km and use online converter to calculate mpg. I totally forgot about different galons.

So my bike consumes about 4,3 to 4,8 liters per 100km.

Previously I owned street bike with pitbike engine (155cc) which while not being perfectly tuned and having only four gears (which led to riding constantly on high rpms) wouldn't burn more than 3l/100km regardless of aggressiveness of driving.

From what I know of average fuel consumption I expected about 3 to 3,5 liters per 100km from my 200c bike.

Fun fact: while buying this motorcycle I decided to get 200cc not 250cc mainly for fuel economy.

culcune · 08-18-2019, 10:55 AM

If it is US gallons, I had a TMEC 200 dual-sport (TMEC's engine OEM is Zongshen) which got about the same fuel consumption as you. I commuted to work daily on the bike, 33 miles round-trip daily at 55 miles per hour or faster for most of the commute.

bogieboy · 08-18-2019, 12:42 PM

same here, my roketa averages 55-60mpg (us gallons) whn driving flat out averaging 45-55mph.

Rozkrwawiacz · 08-18-2019, 01:49 PM

Ok, maybe I wasn't precise. I do believe that it is possible for engine this size to consume that amount of fuel. On the same time it is also possible for 50cc to use 5l/100km if tuned badly enough. I wouldn't call it "burning" then, though.

When I bought it it was consuming 5l/100km, but since then I tuned carb and replaced piston rings. Also started to pump more air into tires. I allowed it to decrease thirst for fuel significantly but still not enough for what, imao, properly tuned 200cc should be burning.

Chinese bikes usually use same kind of engines, dual-sport or not it shouldn't use this much fuel unless there is something wrong with it.
F.e. weak spark, missfires, bad mixture, gas tank leakage, carb leakage, worn out piton rings, low tire pressure, slipping clutch, brakes pads touching discs, clogged air filter...

Not all of those symptoms are easy noticeable nor are they preventing from riding on daily basis. Engines don't just burn significantly more fuel than others of the same model without a reason.

Wild Dog · 08-18-2019, 02:34 PM

Quote:

Originally Posted by Rozkrwawiacz

Ok, maybe I wasn't precise. I do believe that it is possible for engine this size to consume that amount of fuel. On the same time it is also possible for 50cc to use 5l/100km if tuned badly enough. I wouldn't call it "burning" then, though.

When I bought it it was consuming 5l/100km, but since then I tuned carb and replaced piston rings. Also started to pump more air into tires. I allowed it to decrease thirst for fuel significantly but still not enough for what, imao, properly tuned 200cc should be burning.

Chinese bikes usually use same kind of engines, dual-sport or not it shouldn't use this much fuel unless there is something wrong with it.
F.e. weak spark, missfires, bad mixture, gas tank leakage, carb leakage, worn out piton rings, low tire pressure, slipping clutch, brakes pads touching discs, clogged air filter...

Not all of those symptoms are easy noticeable nor are they preventing from riding on daily basis. Engines don't just burn significantly more fuel than others of the same model without a reason.

You should recheck the carb, also why did you change the piston rings?? Used bike??

Rozkrwawiacz · 08-18-2019, 04:58 PM

Thanks for all replies

@Wild Dog
Yep, bought it last December. Was burning a little oil and compression was decreased. Wasn't running all that bad before but since runs great. I hoped it would solve spitting oil through breather but it did not. It doesn't spit much and thought about using longer breather hose (current have about 10cm) or that maybe oil is not dense enough.

I tuned carb so it run the best. Had great throttle response and all, but it was tested only in city (so up to about 40mph). Then when I went on trip to another town I believe that engine was overheating due to lean condition (clean spark plug with discolored ring, as if from high temperature), which was redeemed by lowering needle clip. It seems to run worse so I suspect that main jet may be too lean.
But the point is, that with lean condition fuel consumption was still above 4,2l/100km, so it's unlikely that bigger jet will help with that, unfortunately.

What do you think about old rubbers? Could it matter much? Also my rear wheel is suspected of being tilted a little, could that change a lot?

OneLeggedRider · 08-18-2019, 10:39 PM

Why is fuel consumption so important to you? 55mpg is quite acceptable for these bikes. I have a big bore 400 2-smoke that has a huge fuel tank that might last you 3 hours at most. I also have a big Chevy truck that gets 8mpg on the highway on a good day. Even my daily driver, a Toyota 4x4 only gets 12mpg. Gotta pay to play.

08-17-2019, 02:11 PM	#1
Rozkrwawiacz Join Date: Aug 2019 Posts: 10	200cc consumes higher amounts of gas that I would personaly prefer. Hi. I own 2006 Skyteam ST200. It's a Chinese dual-sport with 163FML OHC engine. My biggest problem with it is it's thirst for petrol. It's average is about 55 mpg. I am no newbie when it comes to china motorcycles, so I checked all obvious reasons (like losing gasoline from tank, low tire pressure, and bad tuning) also replaced carb (pz30) and spark plugs and cables, but here I'm helpless From now on I will ignore post regarding fuel economy expectations since they're essentially OFFTOPIC. If you don't want to help solve the problem, because you don't brlieve that there's a problem that's fine, just don't post in this thread, please. Last edited by Rozkrwawiacz; 08-20-2019 at 04:49 AM. Reason: Making some things clear
	0

08-17-2019, 06:22 PM	#3
Red Hawk Join Date: Jul 2018 Location: NEPA Posts: 273	About the same here up & down hills. __________________ 2018 Hawk P&P Decked .040 off the head. 17/43 D.I.D. 428, NGK Iridium plug, DeCat, Wrapped pipe, Custom S.S. Muffler core, Nibbi PE30 115/35, L.E.D. Lights, Digital Cluster, USB port, Cutting Bord skid plate, Oil cooler w/ custom CRF oil filter inline, 5Wt fork oil, Rear Shock, CNC Back Rack, 30mm FAT bars, Bark Busters, ProGrips, Adjustable levers, Shinko 700’s lots of Loctite!
	0

08-18-2019, 05:02 AM	#9
Rozkrwawiacz Join Date: Aug 2019 Posts: 10	@paulsstag Well, you got me. I think in l/100km and use online converter to calculate mpg. I totally forgot about different galons. So my bike consumes about 4,3 to 4,8 liters per 100km. Previously I owned street bike with pitbike engine (155cc) which while not being perfectly tuned and having only four gears (which led to riding constantly on high rpms) wouldn't burn more than 3l/100km regardless of aggressiveness of driving. From what I know of average fuel consumption I expected about 3 to 3,5 liters per 100km from my 200c bike. Fun fact: while buying this motorcycle I decided to get 200cc not 250cc mainly for fuel economy. Last edited by Rozkrwawiacz; 08-18-2019 at 01:50 PM.
	1

08-18-2019, 10:55 AM	#10
culcune Join Date: May 2006 Location: Yuma, Arizona Posts: 9,035	If it is US gallons, I had a TMEC 200 dual-sport (TMEC's engine OEM is Zongshen) which got about the same fuel consumption as you. I commuted to work daily on the bike, 33 miles round-trip daily at 55 miles per hour or faster for most of the commute. __________________ "They say that life's a carousel, spinning fast you got to ride it well..." TGB Delivery Scooter 150 TMEC 200 Enduro--carcass is sadly rotting in the backyard
	0

08-17-2019, 04:26 PM	#2
OneLeggedRider Join Date: Nov 2018 Location: Stockport, Oh. Posts: 1,442	Ehh, that's about what my Hawk gets.
	0

08-17-2019, 06:50 PM	#4
Wild Dog Join Date: Dec 2016 Location: Argentina Posts: 756	Absurd?? That's just slighlty higher than avg. Mine consumes about 70 mpg, so your is not that much, maybe you are just a bit too rich.
	0

08-17-2019, 07:59 PM	#5
Rozkrwawiacz Join Date: Aug 2019 Posts: 10	@Wild Dog Yeah, I would love 70mpg. It seems to be avg. for 250cc AFAIK It is about 25%. Just slightly rich shouldn't cause that much of increase. And I'm not running rich. In fact I was actually running dangerously lean for some time but it did not seemed to affect mpg. @Red Hawk I get it on pavement, between towns. (actually town or out of town results are similar) @OneLeggedRider Isn't Hawk a 250cc?
	0

08-18-2019, 12:42 PM	#11
bogieboy Join Date: May 2013 Location: finger lakes NY Posts: 2,042	same here, my roketa averages 55-60mpg (us gallons) whn driving flat out averaging 45-55mph.
	1

08-18-2019, 01:49 PM	#12
Rozkrwawiacz Join Date: Aug 2019 Posts: 10	Ok, maybe I wasn't precise. I do believe that it is possible for engine this size to consume that amount of fuel. On the same time it is also possible for 50cc to use 5l/100km if tuned badly enough. I wouldn't call it "burning" then, though. When I bought it it was consuming 5l/100km, but since then I tuned carb and replaced piston rings. Also started to pump more air into tires. I allowed it to decrease thirst for fuel significantly but still not enough for what, imao, properly tuned 200cc should be burning. Chinese bikes usually use same kind of engines, dual-sport or not it shouldn't use this much fuel unless there is something wrong with it. F.e. weak spark, missfires, bad mixture, gas tank leakage, carb leakage, worn out piton rings, low tire pressure, slipping clutch, brakes pads touching discs, clogged air filter... Not all of those symptoms are easy noticeable nor are they preventing from riding on daily basis. Engines don't just burn significantly more fuel than others of the same model without a reason.
	1

08-18-2019, 04:58 PM	#14
Rozkrwawiacz Join Date: Aug 2019 Posts: 10	Thanks for all replies @Wild Dog Yep, bought it last December. Was burning a little oil and compression was decreased. Wasn't running all that bad before but since runs great. I hoped it would solve spitting oil through breather but it did not. It doesn't spit much and thought about using longer breather hose (current have about 10cm) or that maybe oil is not dense enough. I tuned carb so it run the best. Had great throttle response and all, but it was tested only in city (so up to about 40mph). Then when I went on trip to another town I believe that engine was overheating due to lean condition (clean spark plug with discolored ring, as if from high temperature), which was redeemed by lowering needle clip. It seems to run worse so I suspect that main jet may be too lean. But the point is, that with lean condition fuel consumption was still above 4,2l/100km, so it's unlikely that bigger jet will help with that, unfortunately. What do you think about old rubbers? Could it matter much? Also my rear wheel is suspected of being tilted a little, could that change a lot?
	0

08-18-2019, 10:39 PM	#15
OneLeggedRider Join Date: Nov 2018 Location: Stockport, Oh. Posts: 1,442	Why is fuel consumption so important to you? 55mpg is quite acceptable for these bikes. I have a big bore 400 2-smoke that has a huge fuel tank that might last you 3 hours at most. I also have a big Chevy truck that gets 8mpg on the highway on a good day. Even my daily driver, a Toyota 4x4 only gets 12mpg. Gotta pay to play.
	0