Rough Running

[TONYO]

OK.....Nice weather so I ride up n down the mountain a few times. Its only 930 ft. SO....Its not a very big mountain! As I come down the last time I let the engine brake it a tad in 2nd. gear. All the other times I let it coast.I stop n look around a bit and got ready to head back home.It was slow crankin....Like it was not gettin enough gas.But it started.....As Im going up n down a few hills it goes back n forth between engine brakin and excelerating.All while im holdin it at one RPM. After I got back on kinda flat ground it quit and has ran great since.It has done this b/4 aprox. 3 years ago......Almost in the same spot! It is a 2014 ST with 30000 miles and I always run 93 gas. Anybody have any idea whats goin on? Kinda scared me.....Thought o chit......Its gona leave me sittin! AND......It has started showing 1000 more RPMS than its runnin on the dial.It is correct on the dig.gage.....It has done this b/4 as well.Anybody else have this issue? :yikes: TIA Tony

[spyderyderjim]

Sounds like your ST 998cc v-twin engine is running lean. Suggest you have new gas filter installed (30000 miles it is due).
Buy a can of Sea Foam injector cleaner, dump in gas tank to clean out fuel injectors a little.
If you have the small 1/8" vacuum hoses to map sensor (like on 998 V-twin engine RT's) , they need to be replaced, (left side of ST as sitting on Spyder).
May as well have a new air filter installed also.
Hope this helps you in right direction to solve lean running condition.
Jim

[Snowbelt Spyder]

Sounds like your ST 998cc v-twin engine is running lean. Suggest you have new gas filter installed (30000 miles it is due).
Buy a can of Sea Foam injector cleaner, dump in gas tank to clean out fuel injectors a little.
If you have the small 1/8" vacuum hoses to map sensor (like on 998 V-twin engine RT's) , they need to be replaced, (left side of ST as sitting on Spyder).
May as well have a new air filter installed also.
Hope this helps you in right direction to solve lean running condition.
Jim

Perfect advice.

[Easy Rider]

It was slow crankin....Like it was not gettin enough gas.But it started.....

Cranking slow is a sign of a battery problem or loose connection......NOT of a fuel problem.

And how do you know what the "correct" RPM is ??

Side note: A dose of fuel system cleaner is a good idea each year after winter "storage".

[Chupaca]

Gonna agree with "Spyderyderjim and TONYO" on this. This should get you back on a smooth ryde again...:thumbup:

[TONYO]

I know at aprox. 48 mph in 3rd. it usually is runnin aprox.4800 rpm. So when I see it all of the sudden showin 5800 rpm at that speed
n gear it is wrong. As far as the slow crank.....I could smell gas after it cranked.The battery is 3 months old and always on a tender. TY For the input.

[TONYO]

TY.....This has only happened twice.And in the same spot after lettin it engine break down the hill. The first time it only had aprox. 10000 miles on it. Other than this it runs great. Ive put 60 miles on it since this happened and it cranks n runs great. Thanks again for the input.