Lmas pipes jetting on 84 RD 500

General forum on engines, transmissions, gearing and modifications to each

Moderator: rztom

Post Reply
Message
Author
Motolli
Posts: 73
Joined: Tue Apr 18, 2017 7:10 am

Lmas pipes jetting on 84 RD 500

#1 Post by Motolli » Mon Jul 31, 2017 4:26 am

Hello folks,

after installing nice new Lomas pipes on my 84 RD 500, the bike was running poor -> stumbling at low revs ( but much better than with stock pipes ) and lean plugs. After some testing and excessive mounting sessions this weekend, I ended up with this:
main jets 180 front / 185 rear ( was 160 / 165 )
air jet 1.4 ( was 1.1 )
pilots 27.5 ( was 30 )
needles 4L10 ! middle clip

It runs smooth from idle, only very light 2-stroking between 3 and 4000 ( without mechanical hacking of gear and chain ), and then very smooth like a cat up to the end. Perfect ! plugs are nice dark black to brown, and dry .
Moving the needle one clip down was not good -> bad throttle response from idle , so I went down with the pilot jet from 30 to 27.5.
The carbs setup was special made by Armin Collet, but now it is better then before. Keep in Mind the 4L10 Needles as good option vs 5L0, because they are perfect without any rework.

best regards
Oliver

Andy500R
Posts: 173
Joined: Thu Jun 27, 2013 5:14 pm

Re: Lmas pipes jetting on 84 RD 500

#2 Post by Andy500R » Mon Jul 31, 2017 3:24 pm

My jL pipes arrived this week
I have rebuilt engine and will
Be using lance gamma filters
I'm thinking i might need about
220 mains ,if your on 185s I guess
I'll have to see how it runs ,good
Info though cheers ?

Motolli
Posts: 73
Joined: Tue Apr 18, 2017 7:10 am

Re: Lmas pipes jetting on 84 RD 500

#3 Post by Motolli » Tue Aug 01, 2017 6:12 am

My air box and filters are normal stock
I was just following some topics here in the forum and that works fine;-)

Post Reply