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Low RPM throttle instability / surging

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I have a stock 09 Honda CRF 450X, and I am having trouble keeping a steady speed when trying to cruise down the road at about 15-20mph.

The engine either wants to either accelerate, or deccelerate when I'm trying to maintain a low speed. It's annoying, but otherwise the bike runs good.

Any suggestions?

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I have a stock 09 Honda CRF 450X, and I am having trouble keeping a steady speed when trying to cruise down the road at about 15-20mph.

The engine either wants to either accelerate, or deccelerate when I'm trying to maintain a low speed. It's annoying, but otherwise the bike runs good.

Any suggestions?

- Is your jetting stock?

- Is your motor broken in properly?

- Have you adjusted your fuel screw?

- Is your gas fresh?

- Is your airbox and exhaust stock?

- are you in too high of a gear?

The X responds well to a Jetting change, and an exhaust mod.

It responds REALLY well to a Accelerator pump linkage spring upgrade.

If you want rock steady throttle response at all rpms and all loads, then you need to upgrade to the R&D Powerbowl II. http://www.r1dean.com/cart/index.php?main_page=product_info&cPath=1&products_id=66

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- Is your jetting stock?

- Is your motor broken in properly?

- Have you adjusted your fuel screw?

- Is your gas fresh?

- Is your airbox and exhaust stock?

- are you in too high of a gear?

The X responds well to a Jetting change, and an exhaust mod.

It responds REALLY well to a Accelerator pump linkage spring upgrade.

If you want rock steady throttle response at all rpms and all loads, then you need to upgrade to the R&D Powerbowl II. http://www.r1dean.com/cart/index.php?main_page=product_info&cPath=1&products_id=66

...... Ever feel like a broken record?! 👍

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Yes, everything is stock on the engine, no mods or adjustments done. I have broken it in according to dealer instructions, and the gas is fresh, highest pump octane. I guess the next thing is to adjust the fuel mixture? I'm in second gear at that speed, which feels the right range for it. It's just at the point where I want to cruise, the throttle will either make it accelerate or deccelerate.

I have done searches here for other posts on this, but haven't found one that addresses my particular problem. Maybe I'm just not putting in the right keywords.

I'll try mixture and jetting next......

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I found this happening to my bike (I've got the JD kit) turned out to be the decompressor clearance. But if I were you I'd open it up to breathe and drink better first ie 165 on main jet.

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Yes, everything is stock on the engine, no mods or adjustments done. I have broken it in according to dealer instructions, and the gas is fresh, highest pump octane. I guess the next thing is to adjust the fuel mixture? I'm in second gear at that speed, which feels the right range for it. It's just at the point where I want to cruise, the throttle will either make it accelerate or deccelerate.

I have done searches here for other posts on this, but haven't found one that addresses my particular problem. Maybe I'm just not putting in the right keywords.

I'll try mixture and jetting next......

The stock FCR carb float bowl is part of the problem. But, changing jetting and uncorking will address 80% of all issues. Stiffer apump return spring gets you closer to throttle nirvana...

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