View Full Version : oil injection/pre-mix

05-06-2006, 06:57 AM
I just purchased a used 2003 RS50. The previous owner had instaled a TP 75cc kit, larger carburator, different pipe. When I picked it up, he said that I needed to run between 1-2 ounces of oil per gallon in the gasoline (pre-mix) IN ADDITION to the injection as the injection is insufficient with the 75cc kit. I can't seem to find any information on this. I have read all the paperwork he gave me and I can't find anything about this. Anybody have any experience with this? Thanks for your help.

05-06-2006, 01:22 PM
For anyone who is interested: according to Micah Shoemaker at AF1, running 1.5 ounces (one and one-half ounces of oil) per gallon of gasoline premix WITH the oil pump, brings the ratio back to where it should be as the 75cc kit effectively DOUBLES the air volume.:worship:

05-06-2006, 04:52 PM
I cant tell you how much you need to mix if i do not know your Carburetors size.
A Red TP 75cc kit can run with out extra oil perfectly fine on a carburetor size up to 19mm and a mainjet of 86mm
On my last setup it ran fine with just 1:100 Premix and that was with a 24mm Mikuni and a 200-mikuni mainjet.
Here are the specs.

Its stock now again with some small tuning of the stock cilinder to make it posible to drive 30mph instead of 25mph since they changed the maximum speed for mopeds here from 25mph to 30mph.

05-17-2006, 02:46 AM
a shop that used to be near me used to kit rs50's and would primarily use tp75, arrow pipe, and 24mm carbs. They just turned up the injectors all the way and told their customers to use a high grade oil.
However, i recently just did the same combo except with a malossi 80 stree kit. I have been running the injector turned up along with 2 ounces per gallon. Now that the top end is loosened up I will prob drop it down to 1.5 ounces per gallong. running only the injector seems kinda nuts to me, but i know many have had success doing it.

05-17-2006, 06:06 AM
With a 24mm and a +-200 mikuni mainjet you just ad 100ml/cc to the fuel wen you had to switch to reserve and fill the tank up, should make 1:100 or 1% mixture in the tank extra.

I would recomend to mix even a little bit richer (1:80) on the mixture for RS50 build after 2000 because of the new emision rules that went in than for Europe the oilpumps after 2000 gave a little bit less oil.

Keep in mind the bigger the mainjet is that your using the more oil needs to be added to keep the same oil/fuel mixture, unless you get rid of the oil pump and mix 1:35 premix your self.

Also if you ad premix to the fuel you will need to increase the jet size slightly acording to the % of oil added to the fuel, so 3% premix will mean a +-3% bigger jet.
Sometimes just adjusting the air/fuel mixture screw will be all thats needed.