www.DRRiders.com-2024 Need help! Bad gas? (2024)

Jeremy P 122 Newbie Jeremy P 122

4:33 PM - 2 days ago#112024-05-19T16:33+00:00

Marseivix wrote: ↑
4:30 PM - 2 days ago
I've heard that gas can start to pool in the intake manifold if it's running rich at idle, which might explain the stumble the first time you give it throttle. When you turn the pilot screw all the way in with the engine running and fully warmed up, does it stop running entirely?

Interesting, that could make sense. I honestly don’t have a good way to mess with the screw while it’s running. Idk how you guys do it lol.

EDIT: I will not though I had the screw at 2 full turns and it was not doing this before I got that gas. Turned it to 1.5 and it was doing a loud pop on decel when shifting up. So just moved it back out to 2 this morning and that pop is gone. Stumble has remained throughout

Marseivix 2214 Newbie Marseivix 2214

4:36 PM - 2 days ago#122024-05-19T16:36+00:00

I put a towel down over the engine and use a slotted screwdriver bit in a 1/4 in socket to turn it (with gloves on). It's not the best, but it works well enough for me.

Fast Company 90131 Trail Rider Fast Company 90131

6:09 PM - 2 days ago#132024-05-19T18:09+00:00

Like MXRob and others, I've done a lot of experimenting with different carb kits and needles with our AFM and have been able to get the BST carb to work amazingly well. Gleaning knowledge from these and other real world carb related experiments I have painstakingly typed out a step by step guide on how to eliminate the quirky BST carb related issues [such as off idle stumble and high speed surging among others] as my contrubution to DRRiders and will copy paste it below. *Be sure not to skip ahead or miss any of the steps

Step 1: Remove BST carb and chuck it in the garbage
Step 2: Install ProCycle's TM40 carb as per instructions
Step 3: Smile and open a celebratory beer

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Pemby Moto 4341,296 SuperMoto Dude Pemby Moto 4341,296

6:10 PM - 2 days ago#142024-05-19T18:10+00:00

If it only started with that gas the symptoms sound very much like it could be water in the gas. Easiest solution to find out is to drain, refill and run a couple tanks through to see if it goes away.
Always start with if it was running fine before what changed.

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Fast Company 90131 Trail Rider Fast Company 90131

6:37 PM - 2 days ago#152024-05-19T18:37+00:00

Wouldn't hurt to splash in some sea Foam or Isopropyl along with the fresh gas

Jeremy P 122 Newbie Jeremy P 122

7:50 PM - 2 days ago#162024-05-19T19:50+00:00

Thanks guys. At this point going to ride it a bit and see if it goes away. Also going to work on adjusting idle speed.

If all else fails I may get an Acerbis tank and and that new carb, haha

SumoAustin 1,1461,638 Adventure Rider SumoAustin 1,1461,638

8:41 PM - 2 days ago#172024-05-19T20:41+00:00

You don't grind the plastic spacer unless you switch to one of the short dynojet needles. A standard length needle should have the full circle plastic spacer and it will rest on top of a D shaped shelf inside the carburetor. It's done that way so the needle hangs at a slight angle by design. If you ground your spacer so it doesn't sit on that shelf then your needle is way too low.

I didn't have time to write a short post so I wrote a long one instead.

wasrupzuk 5661 MSF Student wasrupzuk 5661

11:36 PM - 2 days ago#182024-05-19T23:36+00:00

Just a guess.
Move the secondary air filter away from the air box opening and ensure the hose isn’t kinked.
I think the air entering the air box is effecting the secondary air filter, I’m guessing that the rpm is picking up slightly after this as the engine recovers so when you twist it a second time it just enough to overcome the vacuum being applied to the secondary air filter.
The snorkel would help minimize this by pulling clean air away from the second filter, remove it and it’s possible to do this.
That said, Fast Company nailed it in steps 1,2&3.

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rustynut2 209234 Single Tracker rustynut2 209234

1:00 AM - 2 days ago#192024-05-20T01:00+00:00

From my quick read through, You set the idle mixture at 2 turns out but you should set it at the highest/smoothest setting at a low idle speed when warm. Not just a random number of turns out. I think you are rich at idle. Setting the needle depends on climate and altitude along with air box modifications. Don’t grind anything or make any major changes till it runs proper as is, it will only make things worse.

Work harder, millions on welfare depend on you
23 DR650

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Jeremy P 122 Newbie Jeremy P 122

1:56 AM - 2 days ago#202024-05-20T01:56+00:00

wasrupzuk wrote: ↑
11:36 PM - 2 days ago
Just a guess.
Move the secondary air filter away from the air box opening and ensure the hose isn’t kinked.
I think the air entering the air box is effecting the secondary air filter, I’m guessing that the rpm is picking up slightly after this as the engine recovers so when you twist it a second time it just enough to overcome the vacuum being applied to the secondary air filter.
The snorkel would help minimize this by pulling clean air away from the second filter, remove it and it’s possible to do this.
That said, Fast Company nailed it in steps 1,2&3.

Good thought but I’ve checked and the filter is way clear of that snorkel hole and not kinked.

Trying not to drop anymore money but I hear you about the BST lol.