Pilot jet size and bogging down

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Timspu
Posts: 52
Joined: Fri Nov 18, 2005 10:59 pm
Location: Devon, UK

Pilot jet size and bogging down

#1 Post by Timspu » Tue Jun 13, 2017 9:27 am

My machine is back on the road with standard jets, 195 mains and 22.5 pilots, needles in mid position. (Standard exhausts and air box)
When the throttle is opened up from idle the engine is very slow to pick up, once above 2500 rpm she free revs beautifully. Pulling away at low revs the engine tends to want to stall so slipping clutch and applying more throttle works.
I have checked the plugs and they are not dark enough, light grey to light brown. The bike pulls well with power up to the red line and through. Its just a bottom end issue on the on part throttle. Would going to 25 pilot jets help with this?

I did originally start with Nikon expansion chambers and the part throttle issue was not there. The bike has poor power response until 9k and then pulled hard right through the red line. As this was a waste of time i fitted the standard exhaust pipes and now have the part throttle issue.

Any thoughts would be appreciated, my current plan is pilot jets to 25 and main jets to 200 as it appears to be lean.

Thanks

TIM

Timspu
Posts: 52
Joined: Fri Nov 18, 2005 10:59 pm
Location: Devon, UK

Re: Pilot jet size and bogging down

#2 Post by Timspu » Sun Jun 18, 2017 4:01 am

Fitted 27.5 pilot jets. Noticed main jets were already 200's. As I am in there have fitted 210's. Bike started fine with a little choke and throttle response is instant. No more bogging down. Next step test drive, hopefully it's not too rich.

Timspu
Posts: 52
Joined: Fri Nov 18, 2005 10:59 pm
Location: Devon, UK

Re: Pilot jet size and bogging down

#3 Post by Timspu » Sun Jun 18, 2017 1:15 pm

Bike pulled fine till 5k RPM then lots of clutch slip. Still got it home and pulled the plugs to find them a nice choco brown colour.
Now to sort the clutch out, it's adjusted correctly to the manual. So ordered HD clutch springs.

Timspu
Posts: 52
Joined: Fri Nov 18, 2005 10:59 pm
Location: Devon, UK

Re: Pilot jet size and bogging down

#4 Post by Timspu » Tue Jul 04, 2017 3:22 pm

Have adjusted needles to mid slot and pulls fine now. Carbs all sorted.

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two-stroke-brit
Posts: 294
Joined: Wed Jul 24, 2013 11:07 pm
Location: Houston tx

Re: Pilot jet size and bogging down

#5 Post by two-stroke-brit » Thu Jul 13, 2017 2:02 pm

sounds like you are on the right track :grin:
She might not be pretty but always a fun ride !!

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