Start up premix ratio?

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GT750Battleship
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Re: Start up premix ratio?

Post by GT750Battleship »

I wonder how Suzuki did a "First Start" at the Factory ! I can just about guarantee that they trusted the pump to do the job...never ever heard of running pre-mix as a precaution,could cause things to run lean...defeating the mindset of extra oil :cry:
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Roger
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pearljam724
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Re: Start up premix ratio?

Post by pearljam724 »

As Roger stated. Using the pump with a mixture of 20 or 30:1 is entirely too much oil and the bike will run lean. I would hold the pump wide open or use a 50:1 mixture combined with the pump. Only till you verify pump is working. I like the idea of premix initially. But, if you're using pump also. Tone the premix way down. 50:1 combined with pump is actually too much oil too.
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Re: Start up premix ratio?

Post by Vintageman »

You should verify the pump is working before you fire it up. Just pushing the bike in gear with pump wide open it pumps real fast.
I'll partially empty lines and verify it pumps... only way to be sure is check. On the x50 twins I'll pull side cover and run pump shaft with drill.

Putting a little oil in the tank is only little insurance for a brief period if pump fails (has saved my arse) or for me extra lubriction for the top end if you run them hard or sustained higher rpms. I have had very good luck with doing this. I learned this from others...

It is my understand modern oils burn well and its not the same as simply saying you have just that much less gas: I have seen those articles with but a sentence saying that it is exactly the same.... Not reasonble?

But, here's the kicker, If all you do is added say 100:1 to 64:1 into the tank and you go lean, you were on the edge of too lean and simply a cooler day would expose that problem. :wink:

Yeah I am being anal. But lately doing top end jobs on these old girls is not as easy as pistons and cylinders become rare and who can do bore right is priceless. When I drive don’t want to baby them either... I like to tune them a litlle more than factory too

Also break in seams to be so important and can make or break and engine. Only recently I am appreciating the sensitivity of this step. I am definitely siding on keeping the rpms down low and monitoring the sound of the top end as does its initial break in and even take a look see inside


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Re: Start up premix ratio?

Post by Coyote »

A very competent board member told me once: Start it and bring it up to temp 3 times with total cooling between the 3 runs. Re-torque the head bolts, then ride it like you stole it. I never did that but I did re-torque the head bolts at 100 miles. I was very surprised at how much tension they had lost. This time I am leaving the ram air shroud off for the first 100 miles. To me that shroud was a gimmick. It does more harm than good on a hot day stuck in traffic. It actually traps the heat as opposed to dissipating it.
I was born with nothing and still have most of it left.

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pearljam724
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Re: Start up premix ratio?

Post by pearljam724 »

That's a good point. I never stopped to think about it. I won't let an air cooled bike idle past a minute or 2 past operating temperature.
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Re: Start up premix ratio?

Post by Coyote »

This IS an empty bottle of simple green. That WAS an air hose QD (ground the catch ridge off). This WILL contain the premix for start up. It will hang from a camera tripod This all equals no oil (premix) in the gas tank. I have a couple gallons of fresh ethanol free gas for the tank. Going to the hardware store to see if I can find an on/off valve for this contraption.. Did the same with RedZone except I had a spare oil tank I used. No valve on it either. The neat thing here is when the oil pump proves out, I can dump the bottle and let the engine suck it dry.

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I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
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