Lead Substitute?

[BamaBill]

I've been running my bike with Gunk Lead Substitute since I got it running..... Just wondering if anyone else does? Does it really need it? I know back when these bikes were manufactured most gas was leaded. The owners manual states use 91 octaine leaded gas. Newer engines have valves that are made of different medals and some have soft seals that are designed to be used with unleaded gas. Would running unleaded gas with no substitute cause premature valve damage?
What's ya'lls input on this?

Bill

 

[willem]

I only used unleaded in my bike, and after 85k km on the clock, there are no valve issues.

I'm no expert but I don't think these bikes need the lead substitute

 

[Edgee2004]

what year is your bike?
If you do not have hardened valve seats than you need to use a lead subsitute.
if you have a 80's model bike its a safe bet that you have hardened valve seats.

but to answer your question. if your engine requires lead because you have soft valve seats than not useing a lead substitue will cause perminate damage to the vavles and seats.

 

[xschris]

All of these bikes use un-leaded gas. You don't need to add lead

 

[Edgee2004]

Listen to "xschris".

 

[xschris]

Some of the earlier bikes say leaded, it don't matter. The later models with the same engine say un-leaded

 

[HoughMade]

The feds started un-leading the gas in 1973 or 74. Everything made at that point and after can use unleaded gas without a problem.

[edit]- actually the lead phase-out started in 1971 and vehicles after that date incorporated valve seats to safely use leaded gas.

 

[xschris]

All 4-stroke jap bikes have hardened valves. I have read that using a lead substitute can even hurt the engine by creating lead deposits on combustion parts.

 

[Scorpio1963]

The feds started un-leading the gas in 1973 or 74. Everything made at that point and after can use unleaded gas without a problem.

[edit]- actually the lead phase-out started in 1971 and vehicles after that date incorporated valve seats to safely use leaded gas.

Hemm I didnt know it was that early in the 70`s when the lead fase out began.I thought it was more like 76 on up.
So any bike made after 1976 can be run on unleaded gas.

 

[16VGTIDave]

Lead was phased out of automotive fuels to make way for catalytic converters.

 

[BamaBill]

Thanks guys for your imput! I can't believe they still had labels inside the air box cover on the left side that still read use leaded fuel in 1982.

 

[HoughMade]

Hemm I didnt know it was that early in the 70`s when the lead fase out began.I thought it was more like 76 on up.
So any bike made after 1976 can be run on unleaded gas.

We're talking about 2 different things. You are talking about the mandate that new vehicle MUST use unleaded gas, and you are correct. I am talking about the beginning of the lead phase-out and the initial passage of the legislation so that all the manufacturers knew that lead was on its way out. Most, certainly not all, manufacturers made their vehicles to be able to use unleaded gas without damage long before the unleaded gas mandate took effect. This was so that if unleaded was all you could find, you could use it without fear. Though truthfully, valve seat erosion is a long (very long) term issue and a couple tanks of unleaded over time isn't going to do anything.

 

[Edgee2004]

run unleaded. if it breaks fix it!!!!

 

[HoughMade]

run unleaded. if it breaks fix it!!!!

That's what they all said in the '70s and '80s too. And they were right. Took years for a well maintained car to suffer valve seat erosion.