DR350 Bogs and Dies as soon as i hit throttle

Hey i just got a 1995 DR350SE in non-working condition. It had the classic fuel in the oil problem due to a crappy petcock. rebuilt the petcock and properly connected the vaccum line (i think) and now the bike starts up great and sits there and idles either with choke on or off.

BUT

as soon as i touch the throttle the bike bogs down and dies, if i let off it picks up to idle again.

not sure why this is happening...any advice would be huge.

Thanks!

Does it cold start without choke? If so, the mixture is too rich.

You really should replace the stock petcock:

http://dr350.wikia.com/wiki/Vacuum_petcock

It's possible the petcock is allowing fuel down the vacuum line creating an excessively rich mixture.

As a quick check, disconnect the vacuum line at the carb and seal off the nipple on the carb so it's air tight.

Set your petcock to PRI and see if that helps.

Does it cold start without choke? If so, the mixture is too rich.

You really should replace the stock petcock:

http://dr350.wikia.com/wiki/Vacuum_petcock

It's possible the petcock is allowing fuel down the vacuum line creating an excessively rich mixture.

As a quick check, disconnect the vacuum line at the carb and seal off the nipple on the carb so it's air tight.

Set your petcock to PRI and see if that helps.

Good advise, and if that doesn't work it sure sounds like the pilot circuit is clogged. I suggest you clean and inspect the entire carb.

Good luck and welcome to TT :smirk:

You really should replace the stock petcock:

+1 :smirk:

I'll definitely replace the stock petcock as suggested thanks!

Also can anyone suggest a url to the best guide of how to rebuild the standard carb? i'm new to working on carb stuff and if there's a more helpful guide than my Clymer manual that would be awesome.

thanks!

Also can anyone suggest a url to the best guide of how to rebuild the standard carb? i'm new to working on carb stuff and if there's a more helpful guide than my Clymer manual that would be awesome.

thanks!

Use the BST 40 link,

If you dont see the parts on your BST33 ignore them.

Dont do any of the mods either. :smirk:

http://www.advrider.com/forums/showthread.php?t=347184

I'll definitely replace the stock petcock as suggested thanks!

Also can anyone suggest a url to the best guide of how to rebuild the standard carb? i'm new to working on carb stuff and if there's a more helpful guide than my Clymer manual that would be awesome.

thanks!

The clip may have come off the needle too.

It'll idle but die as soon as any throttle is applied.

so i installed the Raptor 660 petcock as everyone suggests thinking that it would fix the fuel in the oil problem, but it did not. my oil still smells heavily of fuel.

what could be causing this?

The float valve could be leaking or the the floats are cracked. This will adversely affect fuel level in the bowl. Check the fuel level using a clear tube connected to the carb drain:

http://dr350.wikia.com/wiki/CV_Carburetor_tuning

The float valve could be leaking or the the floats are cracked. This will adversely affect fuel level in the bowl. Check the fuel level using a clear tube connected to the carb drain:

http://dr350.wikia.com/wiki/CV_Carburetor_tuning

that's a great idea for an easy check...will do that today and let you know what happened. Thanks so much!

Ok im halfway into following the BST bible here: http://www.advrider.com/forums/showthread.php?t=347184

But i just got stuck because the guide is for a BST-40 and i have the BST-33 because i have a DR350.

1. I can't figure out how to remove the support slide and needle jet because there is no main jet spacer which can be removed to push the needle jet down. It is just set into a housing and threaded as seen in this picture:

BST33-1.jpg

2. Also in the next picture you can see how there is no way to remove the fuel/air screw. the BST40 seems to have a slot for removal with a flatblade. How should i get this out?

BST33-2.jpg

3. And do i need to remove the main jet nozzle, if so how? (my Clymer manual says nothing about how, just says to remove it)

Advice is very appreciated since my carb is now in pieces :ride:

update: just figured that i needed to drill out the metal plug covering the fuel/air screw. so i got that out after a lot of convincing.

but i still can't figure out how to remove the support slide/needle jet assembly thing

update: just figured that i needed to drill out the metal plug covering the fuel/air screw. so i got that out after a lot of convincing.

but i still can't figure out how to remove the support slide/needle jet assembly thing

The main jet screws through the aluminum carb body and into the bottom of the needle jet holding it down in the carb body. They are tight in the body so it might take a bit to unseat it. Use the main jet and screw it all the way in then back it out 1/2 turn. Tap on the end of the main jet with a plastic mallet... once the jet starts moving the jet will tighten up... back it out another 1/2 turn and tap the jet again. I wouldn't tap on the MJ more than one turn out to prevent thread damage to the two components. Once the needle jet moves that far it should push out with a punch after removing the main jet. Be careful.. the needle jet is normally pinned for rotation orientation with a groove in the lower portion of the jet... everything has to line up before tapping the jet back in place... obviously you will want to use something softer than brass to do so.

great advice Rob, thanks so much!!!

i was able to convince it to come out after a few taps. The slide was super hard to get out but i got it.

the needle jet O-ring (with the 4 scallop cut outs in it so it seats on the slide) and the needle valve O-ring and the float bowl O-ring could all stand to be replaced.

do i need to order the OEM ones or will standard fuel grade O-rings work ok as long as they fit? do i need the special scalloped one for the needle jet/slide?

what do you think?

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