I have a 2001 DS with a RW stage 1. I just installed a Pami high compression piston (11.2:1), a set of Pami sport cams (270 D 406 L), clutch springs, valve springs, and a carb mount K&N. My problem is jetting the carb. The beginning of Spring, I put the Ron Wood Stage 1 kit on and that comes with the 45 mm carb, with a 150 main jet. Everything ran really well all summer long. With the new modifications I just had installed, including the K&N on the carb, my plugs looked lean so I jumped to 155, 160, 165, 170 and the plug still looked lean so I went to 175 and had a good pull the whole way up the rpm range till the top end, and then it died. I pulled the plug again and it still looked lean, so I jumped to a 180, 185 and the top end syptoms got worse so I went back to 165, where it ran well the whole way through the rpm range. I thought I had it dialed in pretty well until I went for a ride this weekend and really got on it through the gears and I noticed a popping sound; the engine wasn't pulling smooth kind of stuttering. My plugs still look rather light and I am not sure what to do now. Should I play with the needle at all? It idles good. I run 112 octane with half 89 octane. Thank you very much for your help.

P.S. I live in PA nothing over 2,500ft and its cold (45F-32F)
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Anyone????!!!!

 

Did you put the cams in? Sounds like the valve lash is off. I'd check that 1st to see if you need different spacers.

 

Do you have to run that kind of fuel for that compression? 180 main and richen up the needle.

 

ALL THAT CASH & RUNS WORSE?????????? ...........(now ya did it!)

 

155-165 range is probably where you need to be with the main jet using the 45mm carb. Sounds like you need to raise the jet needle to get the plug to read richer and gain more midrange power. The pilot air screw can be adjusted as well. What size pilot jet do you have? 25 to 35 is probably needed.

I have experienced sputtering that was due to dirt in the carb. Take all jets out and spray carb cleaner.

Are your coil connections tight?

 

I set the valve lash after I put the head back on. They were tight before I started the work, but now there on.


Scooby, do you think I could still be rich with light plugs? I had people tell me that there should be hardly any carb changes after the cams, piston, and air filter on the carb.


One other thing, I was sitting at the bottom of a coal pile (with no runway) and I usualy pop the clutch in 2nd, rev out then hit 3rd and pull the hill with good speed. Now on the shift it bogs and sputters kind of embarrassing around the yams.[img]i/expressions/face-icon-small-wink.gif[/img]

 

I'm not sure I have to run that fuel people tell me yes some tell me no. I run it to be on the safe side. It's average is 99-100 octane

 

Yes, you can be too rich (at full throttle) and have the plugs lean! So I was suggesting that the needle position be richened up (raised) so that when cruising around with new plugs, there is some coloring of the plugs without using full throttle. The tuning of the pilot circuit will help throttle response also.

I just noticed that you went from the stock airbox to the direct clamp-on filter. I think this change is what is causing problems with the 45mm carb. I had better luck with throttle response using the airbox and snorkle with the 45mm carb. You can hurt throttle response by removing the snorkle - the length, diameter and velocity is tuned. What it sounds like you are getting is a temporary lean condition when you nail the throttle from idle - the motor has to start sucking air before it draws gas up through the jets. The carb is suppossed to have an accelerator pump for this reason, but Woods disables it. The accelerator pump is tricky to get working correctly - it dumps a lot of fuel and not very precisely into the engine. Different pump jet sizes are available and the "stroke" of the accelerator pump can be adjusted to stop injecting at different throttle openings.

There are manuals here: www.mikuni.com

 

Lakota,

Have you tried a new set of plugs? I know they shouldn't have gone bad during a tear down but stranger things have happened. Also, check the plug wires and caps, they may have been damaged as you were working on the head.
The ignition demand increases in direct proportion to horsepower output so when you are cruizing around at 1/4 to 3/4 throttle with little load your ignition output is low. When you are climbing hills or otherwise demanding 90% to 100% hp your ignition is also trying to provide 100%. Any increased resistance in plug wires, caps or plugs will cause a reduction in spark quality and the symptoms that you are describing. Its worth checking.