[srini]

Hey guys,
I am not sure if this is appropriate here, I am from India and own a 350cc Iron Barrel Enfield.
I replaced new piston (size 40) with new rings. I am running-in the engine at 40 to 50 kmph max and so far made around 400 kms. I am due in for an oil change at ~500 kms.

After my oil change this weekend I am planning to make a trip, the one way is 180 KM distance.
1) Can I ride the bike at a max speed to 60 to 70 KMPH?
2) Right now I premixed 2T oil with fuel at the rate of 10ML per Liter. Can I premix 2T oil before venturing for this ride to go easy with rings and piston?

Please share your suggestion on what I need to consider running-in the engine at 60 - 70 KMPH speed and breaks I can take, etc.

My 90% of heart says take the bike, but my other part of heart says don't and better take a train. Please advice.

Cheers and Thanks! guys

[ace.cafe]

I think you could do it. However, you should not ride at one single speed while doing it. During running-in, you need to run up and down the gears and be accelerating and decelerating most of the time. So you would want to be doing those kinds of things on the long ride too. If you can take a break every half hour to let it cool off a little bit, that would be good. Otherwise, make sure that you have good air flow on the engine, and don't ride close to vehicles in front of you that block the air. It needs good cooling.

[srini]

Thank you Ace for your valuable suggestion!
I am using the highway (motorway) mostly there won't be traffic or vehicles blocking the airflow.
I assume during my ride an average temp in the highway will be in and around 24 deg Celsius.
Do you suggest me to take a 5min break after 40 min ride?
Also on the gearing part (I have 4 speed gearbox), lets say I am on 60 KMPH on 4th gear, can I vary the speed by bumping the gear 1 down and stay on 40 to 50 for sometime?

Your answer will set a good guide to my ride.

Cheers

[RGT]

since you'll be on the highway maybe you could take some exits and get right back on just for the exercise of running it down through the gears and then back up to keep from running at a steady speed....take the bike

[ace.cafe]

Thank you Ace for your valuable suggestion!
I am using the highway (motorway) mostly there won't be traffic or vehicles blocking the airflow.
I assume during my ride an average temp in the highway will be in and around 24 deg Celsius.
Do you suggest me to take a 5min break after 40 min ride?
Also on the gearing part (I have 4 speed gearbox), lets say I am on 60 KMPH on 4th gear, can I vary the speed by bumping the gear 1 down and stay on 40 to 50 for sometime?

Your answer will set a good guide to my ride.

Cheers

It's very hard to say exactly. The factors must not overheat the engine, so that the piston does not seize in the bore. I don't know how much clearance that piston was installed with, nor how much it expands, nor how perfectly the tuning of carb and ignition are, etc.
You just need to monitor the temp of the bike, and give it time to cool off when it needs it. There is no prescribed time or speed. It is judged by the temperatures of the engine, mostly on the head and barrel fins. If it seems to be running hotter than normal, you need to take a break until it has time to cool. I don't think 5 minutes of rest is enough, if the engine is too hot when you stop.
I would advise leaving at least an hour early, and taking your time, and don't try to rush the ride.

[Arizoni]

I've not heard of using a fuel & oil pre-mix in a 4 cycle engine.

It is common in two stroke engines but a 4 stroke engine not only doesn't need the extra oil but IMO, using it can lead to a build up of carbon in the combustion chamber and fouling on the spark plug (not to mention a blue haze clouding up the air behind the motorcycle.)

[motomataya]

It also makes the bike run leaner, therefore possibly hotter.

[srini]

Thank you Arizoni, Motomaya & RGT

@RGT, getting down the exit for a short break is a nice idea. My dad still insist me to take a car or train. His opinion on making 60 - 70 KMPH speed on open highway is too boring. I started to feel the same, but still I am on full mood to take the bike.

@motomaya - Even my mech said, add 2T on two fills, after that just pure petrol. He too mentioned about leaning the mix.

@Arizoni - It's usual practice here in India, after a new build, or new piston, the mech usually drops 10ml oil for 1 Liter of petrol. I do agree with your statement on fouling the spark plug, it indeed happened to me yesterday. I did second fill up with less amount of 2T this time. Going further I will use pure premium petrol.