Aprilia RS 125 New Engine

ARS125 · Two Stroke Sniffer Joined: 02 Aug 2017 Karma :

Picked up a unrestricted 2003 Aprilia RS 125 with 20k on the original engine. New engine fitted with about 80 miles on so far.

Apparently you should keep the revs below 6k for the first 500 miles. 500 MILES! I've researched and the opinion seems to be debatable. Some say just warm the bike up and after 100 miles thrash away. Others say your going to blow the engine if you go over 6k in the first 500 miles.

Limiting the revs to 6k makes it hard to even reach the speed limit of most roads.

What is actually required on these new engines? does the 100 mile thing work?

Being my first real 2 stroke bike its still all very new to me. As a side question are these RS 125 bikes suitable for fairly long rides? say 50 to 100 miles or do long rides risk damage? I'm not talking huge miles but i do regularly do 50 to 100 mile rides.

redeem ouzzer · World Chat Champion Joined: 06 Oct 2015 Karma :

4 x 15 minute heat cycles, then thrash it. You don't think racers run a rebuilt engine in by doing 500 miles of pottering?
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Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

I run them in over quite a distance. 5k for 500km and then build up to the red line over the next 500km. But you pays your money and takes your chances. Roughly 10mph per 1000rpm.

As to 50~100 miles, that is a short journey. Doing it daily might put the miles through the roof quickly though.

All the best

Katy
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P. · Red Rocket Joined: 14 Feb 2008 Karma :

I did 100 sensible miles on my 125, but after about 5 miles or so I used to give it a bit of a handful up to about 9k and let it run itself back down.

Engine was fine.

skatefreak · World Chat Champion Joined: 06 Feb 2010 Karma :

It's a 125 2 stroke... Rings and pistons are basically a consumable with this in mind during engine design (quick and easy to change a piston, engine still in the bike with many) and pricing as well (not expensive for a piston kit).

I would suggest idle for a while, make sure oil pump is working, take it out and just take it easy for a while... Never had any problems with my NSR125 (de-restricted as well).

stevo as b4 · World Chat Champion Joined: 17 Jul 2003 Karma :

I've run the KMX rebuilt engine in over about 280miles, but I could tell by 200miles it was happy. It went on the dyno at the above mileage but would have been sooner if I could have booked it in. Im not a fan or advocate of heat cycles, but short rides and then stopping to check nothing is loose or leaking is a good idea.

Regards the long distances and looking after for a std road going two stroke, do a search we've talked about it on here until we all got old.

Two stroke bikes are about looking after them and not scrimping if they are regular transport. On your RS or anything else I'd do all the following every 2000miles, and stick to good oil, gentle warm ups, and a service life for all the moving parts:

Change plug, new gearbox oil, clean air filter, set up adjust oil pump and carb as required. Replace or clean fuel filters etc etc. All the rest is std maintenance and don't cheap out parts or stretch service life.

An RS125 would love a top end rebuild at 8-9000m, and it'll save you loads over waiting for a bang and buying most of a new engine or having everything reconditioned etc.