Hi I just bought a 2001 DS650 and it starts no problem, lots of juice to the battery, but usually bogs under full acceleration. Plugs have been replaced and airfilter is new etc.

What could make it bog only under full throttle. Now if I slowly open the throttle it works somewhat or if I pump the throttle a bit before a turn lets say it works better.

Anyone have any idea what this is or had a similiar problem. I think I,m going to start by taking the carb apart

 

Crack the gas cap to let some air get in during acceleration and let us know if that worked. If so, your gas tank breather is pinched.

 

Make sure that your tank breather is not clogged. Try pulling off the gas cap and see if that helps... the breather under the tank cover often gets clogged. If the gas cap deal works either get a vented gas cap, or replace stocker. Make sure your tank is flowing as well.... there is a screen in the tank... check it too. Also you could pull the top off your carb and check that your needle is seated properly. I had that issue once... sounded similar. Good luck.

 

... Red you beat me to it.LOL

 

<div class="FTQUOTE"><begin quote>Originally posted by: FatHolly

Make sure that your tank breather is not clogged. Try pulling off the gas cap and see if that helps... the breather under the tank cover often gets clogged. If the gas cap deal works either get a vented gas cap, or replace stocker. Make sure your tank is flowing as well.... there is a screen in the tank... check it too. Also you could pull the top off your carb and check that your needle is seated properly. I had that issue once... sounded similar. Good luck.</end quote></div>


yup tried that, got a crotch full of 91 supreme(tank was full at the time) nothing changed. Is it fairly simple to open up the carb? any tips before the job?

Thanks guys

 

If it is the needle that is popped out then all you need to do is take the gold round piece off the top of the carb. That is where the needle is... pull the diaphram and slide out of the carb. Check the diaphram for rips, and then make sure the needle is seated in the clips in the bottom of the slide. You will be able to tell immediatly if the needle is not seated. The needle will fall out, along with all the washers and stuff. I've seen the clips in the slide break before. If that does not work you will need to pull the carb off and do a good cleaning with carb cleaner.

 

Hi all, just a little update. I got into the carb, noticed some screws were loose on the side where the throttle cable were, dont know if that would be an issue or not.

I then cleaned it and a inspected the areas recommended.

No major issues but there was a bit of dirt.

I did bog less but still nevertheless it did bog under full accel especially in second gear on hill climbs.

So I tried with running the thing with the airbox cover off.

HOLY *****!!! Felt like a new machine. Where I was climbing hills and bogging before I was pulling in 2nd and third.

It flies now without the airbox off. WTF?

So I ordered a EHS Racing airbox cover http://www.ehsracing.com/products/ds650_airbox_EHS.htm


In the mean time I have drilled two silver dollar sized holes in the airbox lid and covered it with a nylon sock. Seems to run fine now, but it still runs better with the lid completely off.

Is this normal or am I only postponing the issue. I watch the colour of the oil and the filter like a hawk to make sure no dirt gets in but other than that is that all it takes to make this run better?

 

It sounds like you were jetted to rich, removing the air box leaned it out.
Pull your spark plugs and see if they are extremely black.

 

Does the bike have an aftermarket pipe and has it been rejetted? Usually after getting a pipe and rejetting it is a good idea to run with the lid off to let in more air.

 

its the stock pipe but by the sounds of it I,m guessing its either blown out or the guts have been removed. I'll have a look. Theres some blackish blue exhaust smoke residue on the sides of the pipe like the seal on the end between the pipe and the exhaust tip is gone. I,m going to take it apart then reseal it.

Could this have been a backpressue issue?

As for the carb I bought the atv used how can I tell if its not stock, I dont know a carb from a cabbage


by the way thanks for all the input