Why does my 2013 RTS have poor acceleration?

Hello, I just joined the forum and need some help. I have a 2013 Spyder RTS SM5 Rotax 998cc engine that will start up just fine. However, when it idles, it will rev back and forth between 1100-1150 rpms then die. I will restart it, and it will stay running. When I put it in Reverse, it struggles when I try to rev the engine, even when I don't release the clutch. On the road, it struggles to accelerate, especially in higher gears, I have to downshift to get power. In some instances when I accelerate it will stall, then suddenly take off. I already replaced the fuel and air filter, and fuel it with 91 octane no ethanol gasoline, with little improvement in the performance. What else could be the cause of this problem? And has anyone else experienced this? Your help is appreciated.

Thank you.

Is it a low mileage bike?

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Originally Posted by Tmeyer14

Hello, I just joined the forum and need some help. I have a 2013 Spyder RTS SM5 Rotax 998cc engine that will start up just fine. However, when it idles, it will rev back and forth between 1100-1150 rpms then die. I will restart it, and it will stay running. When I put it in reverse, it stuggles when I try to rev the engine even when dont release the clutch. On the road, it stuggles to accerate especially in higher gears, I have to downshift to get power. In some intances when I accelerate it will stall, then suddenly take off. I already replaced the fuel and air filter and fuel it with 91 octane no ethanol gasoline with little improvement in the performance. What else could be the cause of this problem?, and has anyone experienced this? Your help is appreciated.

Thank you.

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What else? Vacuum lines to the MAP Sensor. Do a search of the forum. You’ll find info and pictures. Typical 998 issue. Inspect the vacuum line to your clutch assist solenoid, also, to be sure there are no leaks. A dose of fuel injector cleaner won’t hurt, either.

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Originally Posted by BajaRon

Is it a low mileage bike?

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It has 16K

Agree also the purge valve can cause stalls. Topping off gas tank can unfortunately mess it up:welcome::congrats: just in time for Spyders in Ozarks
https://www.lamonstergarage.com/spyd...e_ozarks_2023/

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Originally Posted by Snowbelt Spyder

What else? Vacuum lines to the MAP Sensor. Do a search of the forum. You’ll find info and pictures. Typical 998 issue. Inspect the vacuum line to your clutch assist solenoid, also, to be sure there are no leaks. A dose of fuel injector cleaner won’t hurt, either.

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Thank You, I'll check those out.

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Originally Posted by Tmeyer14

Thank You, I'll check those out.

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I have pics in an Album that shows how I re-routed the Gas line to the EVAP cannister so GAS cannot get into that cannister. .... some folks here just remove the cannister entirely .... Also if you still have OEM plug wires think about trashing them .... they are junk and FAIL early in life .... get the ones from BajaRon .... good luck ... Mike :roflblack:

The shift point on the 998 is at 5500 rpms compared to 3500 on the 1330 engine. You may be under-revving when shifting. A brisk ride at 60 or higher so you can keep it at 5500 rpms at 55-60 might help to loosen things up. The red line on these is 7800 if memory is still good.

On my 998 SM5 I would never use fifth gear until I was into 60 mph or faster. We rented a spyder on Maui back in the day. Drove the 50 mile long Hana Highway totally in first gear. Most of the speed limits were 25 and under.

Ok, I followed Snowbelt Spyder's advise and replaced the vacuum lines on the MAP sensor. They didn't appear to be cracked, but were brittle. I took the Spyder for a test ride and there was an improvement with the acceleration. Still have the problem with the reverse. I have no idea where the clutch assist solenoid is located to check the vacuum line on it. Spark plugs and wires are next.
Thanks to everyone for your help!

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Originally Posted by Tmeyer14

Ok, I followed Snowbelt Spyder's advise and replaced the vacuum lines on the MAP sensor. They didn't appear to be cracked, but were brittle. I took the Spyder for a test ride and there was an improvement with the acceleration. Still have the problem with the reverse. I have no idea where the clutch assist solenoid is located to check the vacuum line on it. Spark plugs and wires are next.
Thanks to everyone for your help!

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I can send you more info once I get back to my computer. In the mean time, you could benefit from doing a canisterectomy. Eliminates another potential failure mode from the purge valve. Many people do it. Do a forum search for that word. All this is on the right hand side of the motor. Plus, plugs and wires are always good. And, you will become intimately familiar with the air box trying to access the front plug.

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Originally Posted by Tmeyer14

Ok, I followed Snowbelt Spyder's advise and replaced the vacuum lines on the MAP sensor. They didn't appear to be cracked, but were brittle. I took the Spyder for a test ride and there was an improvement with the acceleration. Still have the problem with the reverse. I have no idea where the clutch assist solenoid is located to check the vacuum line on it. Spark plugs and wires are next.
Thanks to everyone for your help!

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On the right side of the engine are the components for the clutch assist system. Inspect the rubber lines for vacuum leaks. There should be no continuous vacuum sucking through the vent port when the engine is running. Bottom line is this - heat that is trapped under all of that plastic was the biggest enemy to rubber components on the 998 RT. Not so much mileage. Specifically for the 2013 RT - without going into all of the details - the heat was so bad that it prompted a Safety Recall. So, on your 2013 RT, if you have the scoop looking things underneath of your mirrors, scoops that act like air intakes to direct air under the plastic, then you have had the recall done. If you have just plain looking air deflectors, then you'd better get to a dealer and get the recall done. For the 2013 machine, there was a lot more aspects to the recall than just the air scoops. You can't do it all yourself. It's just that the scoops are the most visible.

If you're not really certain what this all means, then search the forum. Plenty of info and pictures. And all of the documents relating to the recall are on the NHTSA site.

Not really sure why reverse gives you more issues. But, if you feel that your clutch might be dragging just a bit and bogging down the engine, remember that your clutch fluid needs replaced every 2 years. Perhaps you'll just need to catch up on some preventative and corrective maintenance. I 'm assuming that the machine is new to you. Good Luck.

I agree with purge valve. On testing the clutch, a quick test for proper operation is to pull the clutch lever in with the engine off; there should be some resistance. Start the engine and pull the clutch lever in; the resistance should be a lot less. Bruce

Snowbelt Spyder, Thank you for the info. The weird thing about the reverse issue is that when I have the clutch disengaged and I increase the throttle, it struggles to rev up. It does fine in the other gears. It says in the maintenance section of the owner's manual to check the reverse mechanism operation and adjust as needed, but no instructions on how to do it. I'll contact a dealer on the recall issue. You're right, this is a new machine for me!

My problem is solved, it was a fouled spark plug on the right side, heavy carbon build up. Ended up taking it to a shop since getting to that right side plug was going to be a battle. They replaced the plug, cleaned the injectors and checked the fluids. It runs better than the day we bought it 5 years ago!

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Originally Posted by Tmeyer14

My problem is solved, it was a fouled spark plug on the right side, heavy carbon build up. Ended up taking it to a shop since getting to that right side plug was going to be a battle. They replaced the plug, cleaned the injectors and checked the fluids. It runs better than the day we bought it 5 years ago!

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Sounds like the engine might be lugging. A common problem with the 998. Should try to keep it at or above 3,500 RPM at shift and 4,500 running rpm.

I am glad you found the problem. I have a 2021 now, but I do miss the V-twin at times. Bruce

I have been driving mine out in the countryside in 4th gear most of the time, and using my 5th gear like overdrive! That keeps RPM's mostly in the right place.:dontknow: Been working for me!