Just how rich will a carbed Monster run?

bigiain · March 17, 2009, 05:02:46 AM

So I've been putting off changing the needle jets in my '99 M750 - the one that were in there were 80 odd thousand km (~50k miles) old... It was running OK, burbling a popping a bit on overrun, smelling a bit fuelly, and starting real easy without any choke even on cold mornings... So I carefully measured the fuel consumption on the last tank before I swapped them out on the weekend - 7.06L/100km (~33mpg). I just filled it up after having done a couple of hundred km with the new needle jets - 4.92L/100km (~48mpg).

So it looks like I've been using about 40% more fuel than I've needed to lately - the unnecessary fuel I bought for that 2400km trip over new years would have paid for the new needle jets!

It's running quite a bit smoother too now! Takes a lot more babying to warm it up in the morning, and needs choke to start and for the first few km which it didn't need last week...

So it turns out thay'll run _stupidly_ rich, it you let them lull you into thinking they're running OK by only getting rough and "fluffy" gradually over a few years...

lean-and-mean-big

Speeddog · March 17, 2009, 08:46:07 AM

That's quite a bump in mileage.

Did you get the nickel-plated jets?

the_Journeyman · March 17, 2009, 10:55:47 AM

Maybe I should do this. Mine is running quite rich and it's in ggot 31,000 miles. Starts fairly easily without choke ~

JM

ducpainter · March 17, 2009, 06:08:31 PM

Quote from: the_Journeyman on March 17, 2009, 10:55:47 AM
Maybe I should do this. Mine is running quite rich and it's in ggot 31,000 miles. Starts fairly easily without choke ~

JM

That's just not right.

I have almost 30K on my 900 and it probably won't get it's second replacement this year, but next for sure.

beethoven · April 29, 2009, 01:41:05 AM

This thread made me look at my M900 and my fuel economy has been getting slowly worse over the last 3 or so years. Because it still ran well didnt take much notice. So I will bite the bullet and replace the needle jets. Question is do I replace emulsion tubes at same time and is the Factory Pro kit from CA Cycleworks all I need or are there other options.
Thanks for any help.

bigiain · April 29, 2009, 01:56:59 AM

Quote from: beethoven on April 29, 2009, 01:41:05 AM
This thread made me look at my M900 and my fuel economy has been getting slowly worse over the last 3 or so years. Because it still ran well didnt take much notice. So I will bite the bullet and replace the needle jets. Question is do I replace emulsion tubes at same time and is the Factory Pro kit from CA Cycleworks all I need or are there other options.
Thanks for any help.

The needle jets _are_ the emulsion tubes.

I highly recommend the FactoryPro kit, and also Chris @ CA Cycleworks, but (at least when I did mine 7 or 8 years ago) the jet kit doesn't include the needle jets, just the main jets, pilot jets, and needles and springs. The instructions suggest you replace the needle jets before trying to tune it if the ones you've got have got more than 5000 miles on them.

big

beethoven · April 29, 2009, 02:03:32 AM

Thanks Big
Chris has a Factory Pro emulsion tube/needle jet package at $50 per pair. I am only looking at this item for the time being. I have emailed Cycleworks direct to confirm and requested shipping rate to aus.
Alan

bigiain · April 29, 2009, 02:34:00 AM

Quote from: beethoven on April 29, 2009, 02:03:32 AM
Thanks Big
Chris has a Factory Pro emulsion tube/needle jet package at $50 per pair. I am only looking at this item for the time being. I have emailed Cycleworks direct to confirm and requested shipping rate to aus.
Alan

Just in case you're wondering, Frasers here in Sydney were quoting me $120 _ea_ back arouind xmas (and they also said "We've got _one_ in stock it'll be a 6-8 week wait for the other one. Do you want to buy just one?" Yeah, for my single carbed Ducati, right? Idiots...)

big

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Just how rich will a carbed Monster run?