First Time Start Up Procedure

Sonreir

Oregon
DTT SUPPORTER
This post is meant to be a rough guide of things to do (and the order in which to do them) when getting ready to start an engine for the first time. By "first time", I mean after a rebuild or when dealing with an engine whose state or repair/operation is unknown. Each of these steps assume that the previous step has passed successfully. If you encounter any problems, correct the issue and start back at the beginning of the list.

[list type=decimal]
[*]Put the bike into neutral
[*]Double-check all bolts on the engine and ensure they are torqued to spec
[*]Verify engine oil levels. If oil is not fresh, replace it along with the filter.
[*]Gently rotate the engine two full rotations by turning the crankshaft with a wrench. There should be no binding and things should turn easily. The bike should not move. It should get harder when the valves are being opened, but the crank should almost turn away from you as the valves close and exert pressure against the cam. DO NOT force anything if the crank is not turning or if it seems to catch or bind at any point in the process. Verify valves are properly actuating.
[*]Perform timing chain adjustment
[*]Adjust valve clearances
[*]Test compression
[*]Check static ignition timing
[*]Ensure throttle cables are not binding and carb slides move freely
[*]Inspect the intakes to ensure the filters are clean and there is no debris present
[*]Test battery voltage. You should see at least 12.4V on a 12V battery.
[*]Verify you're getting spark by removing the spark plugs from head, reattaching the plug wires, and attempting to start the bike while holding the plugs against the engine case. Replace spark plugs when finished.
[*]Check flow of fuel to the carbs. With the kill switch off, try to start the bike several times (turn electric start for five seconds or kick the kickstart three times). Remove all of the spark plugs and verify each one is wet with fuel.
[*]Turn the kill switch on and start the engine. Allow the bike to idle until the choke is no longer needed to keep it running (should be about 30 seconds). If anything sounds amiss, turn off the engine.
[*]Verify ignition timing with a strobe light. Give the bike some revs and ensure the timing advances properly and to spec.
[*]Once the engine has warmed up, adjust the carb sync using vacuum gauges
[*]After the carbs have been synced, adjust the mixture screws as per the manual
[*]Take the bike for a short ride to ensure that engine is responsive and operations are as expected
[*]If this is a fresh rebuild, follow your favorite break-in procedure
[/list]

If anyone else has anything to add, please do.
 
We remove the tappet covers to make sure oil is getting to the head.


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SaltCityCafe said:
Very last step to any procedure.

Sit back drink beer and admire your handiwork

That's where I've gone wrong... all this time my last step has been, "Take the damn thing apart again and change more stuff".
 
I should add to the "follow your favorite new engine break-in procedure" that the honing of the cylinders is very critical to seating new piston rings. You basically have between the first 20 and 40 miles to utilize the fresh ridges in the hone pattern before they are worn down and glazed over smooth. The rings have imperfections in their shape and surfaces, and need to use the honing pattern as a sort of file to wear some material off of the rings so that they make the best possible seal. If you don't get them seated in that time frame, then it takes a long time of wearing them in to get anywhere close to the possible seal you missed out on right off the bat.

Do everything as stated above, make sure your carbs and intakes have no vacuum leaks, if running a modified setup (pods, exhaust, bigger pistons, cams, etc), find out the jetting and carb tuning specs that others have found to create the best air fuel ratio for that type of setup. Bench synch the carbs, make sure the needles & seats are sealing properly and you have the proper actual fuel level in the bowls. Get your mixture screws, jet needle heights, etc all set as best as you can speculate your new engine will require. It needs to be tuned fairly close from the beginning, as you dont want to waste any time in the first 40 miles of break in.
Once you go through all of the other steps the original poster laid out, and get the engine warmed up to proper operating temperature, take it out to the nearest uncongested roads where you can immediately start accellerating from 30-50mph fairly hard, and then engine brake decelerating back down, over and over at least ten times. The key is to do this as soon as possible after warming the engine up, and never hold a constant throttle position, as you must constantly be exerting accel/decel pressure on the rings as to force them outwards into the cylinder walls.

most break-in procedures tell you to do this on deceleration as well, but I have seen some that just emphasize the acceleration part. you want to do this where the engine makes good power, but you do not want to take it quite to red line at this point yet. It is also very critical not to lug the engine, where you are giving it too much load and more throttle does not do anything much.

other procedures will tell you accelerate&decelerate through the midrange rpm several times, and then do the same procedure only at higher rpm's but still 15% or so below redline. also, it is very critical that you do not use any fancy oils when breaking in new piston rings. absolutely never use synthetic on break in, or early on in the engine's life, say the first hundred or 500 miles. after the first 50 or 100 miles, definitely change the oil. It is debated on what is the best oil to use for break in, but all methods agreed synthetics are a big no no. anything with a whole lot of additives will slow down the ring wear-in/sealing process.

I wanted to emphasize this comment because it is not obvious in many repair manuals, in the factory service manuals will tell you to keep it under a very conservative rpm for the first 500 miles, and then limited to less than red line still for the first 1000 miles. They tell you nothing of how to properly get the rings seated in, probably due to liability of telling someone to go ride it hard right off the bat and for a long duration, doing a break in procedure that will probably a aggravate all other drivers on the road around you as you constantly speed up and slow down.

I mainly posted this just to raise awareness that it is very important to get this break in done within the first 20 to 40 miles, and have the engine running as good as possible immediately right off the bat, especially as far as carburetor jetting is concerned.

best of luck to anyone here starting up their new engine for the first time, used purchase or freshly rebuilt. Thank you to the original poster for starting this thread.
 
Prior to subjecting a fresh engine to any compressive forces such as compression tests or ignition I always build oil pressure on fresh motors with fuel supply off and no plugs in the head. This ensures you have oil flow to all rotating surfaces (ie. Main bearings, cam bearings ect.) prior to running.
 
Hi guys,

quick question. I scored a Honda CB400f for €300 and I am now planning on how to attack the project.

I was thinking of getting it up and running as is.
Afterwards look and design the things I would like to change
Demount
Paint
Mount again.

I was thinking of changing the oil after getting the engine running (oil needs to be warm right to get it all out?) and replace it together with the filter.
At first sight it seems you cannot take out the engine of the frame with the oil filter still mounted, right?

Thanks in advance for your advice!
Nicolas
 
Nicolas G said:
Hi guys,

quick question. I scored a Honda CB400f for €300 and I am now planning on how to attack the project.

I was thinking of getting it up and running as is.
Afterwards look and design the things I would like to change
Demount
Paint
Mount again.

I was thinking of changing the oil after getting the engine running (oil needs to be warm right to get it all out?) and replace it together with the filter.
At first sight it seems you cannot take out the engine of the frame with the oil filter still mounted, right?

Thanks in advance for your advice!
Nicolas

Before start up, I place a heat lamp under engine to warm oil. Drain and change. Im not familiar w 400f, but if it has a filter/screen pull it and make sure it atleast looks clean or clean it.
While waiting for the lamp to warm things up. Pull the plugs and give each cylinder a squirt of penetrant, to ensure the piston rings/cylinders arent running dry.
 
I would say (to the check list at the top) between "Check the flow of fuel", and "Start the engine", you want a "Go and grab a beer or a cup of tea, sit down and look at the bike for 20 minutes, and think about which things you have not done (Nuts / bolts, shit left where it should not be, etc...), then clean up the garage a bit, have another look round, then finally "Start the bike"
 
Before start up, I place a heat lamp under engine to warm oil. Drain and change. Im not familiar w 400f, but if it has a filter/screen pull it and make sure it atleast looks clean or clean it.
While waiting for the lamp to warm things up. Pull the plugs and give each cylinder a squirt of penetrant, to ensure the piston rings/cylinders arent running dry.
This is too funny!
 
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