How much lead additive should I put in 5 gal of gas? Not much into rebuilding the bike so would like to keep my valve seats as long as I can.

No lead !

Hotler, why not? What about the other discussion about how the lead helps cusion the soft valve seats? Wouldn't it be worth the few extra dollars to put the additive in? Or am I missing something?

Hotler is right. The engine is designed for no lead. Lead is a contaminent and can actually build up into spots on the valves. There are no valve rotators on this engine. It can also foul plugs.

These engines run pretty well on mid to high octane gas. I have not tried regular yet and do not plan to but have done half tanks mixed with premium when that is all available with no problems.

I'm no chemist by any means, but I'm running leaded race fuel in my DRZ(unless I can't get any race fuel). I usually run half (leaded)race fuel/half 93 pump. Sometimes I run straight 110 leaded fuel. Whether or not the manufacturer specs out leaded or unleaded bears little affect on the ability of lead to condition the valve seats. Granted, newer engines don't "need" the conditioning like the older engines, but why not try to help it every little bit. Also, with a 12.2:1 comp. ratio, I'm not about to run anything less than 93. I've been running 110 leaded fuel in my DRZ since June. I've never fouled a plug or had any adverse affects whatsoever.


I'm not sure I would run pump gas with an additive in your DRZ. I would go for some quality race fuel that contains lead(if you want to run lead). If I had to choose between unleaded race gas and pump with lead added, I would go with the unleaded race gas. The added quality and consistency of race gas outweighs the need for a cheap lead additive.

That's my $.02. But I'm pretty finicky with my bikes. I also run X1R in my DRZ. It's kind of like cheap insurance to me.(I guess you can call it insurance) :)

[ November 21, 2001: Message edited by: CAL ]

Ok here is my 2-cents worth;

Suzuki has been designing all their bikes around unleaded gas for over twenty years. Their valve seats are known to be very hard. I know Dr. Billz

has had trouble with valves but which end of the valve, the face or the end of the stem where the rocker rides?

I use Phillips 66 101 unleaded race fuel. It's not just the octane it's a better fuel all the way around. Easier starts, better throttle response, cooler running motor, won't turn to varnish in the float bowl, no stablizers needed for storage,consistant guality. At $3.00 a gallon and the milage my "E" gets it's worth it I think.

If you are worried about lubing the top end,(the valve face and seats)try mixing a little castor oil to the fuel (Blendzal or something) about an ounce per five gallons of fuel (read direction on bottle)

The DRZ will run its butt off on street premium, but I notice a difference between the two fuels (street gase and race fuel). If they made a 95 octane unleaded race fuel I'd run it. I run the 101 besause it's the lowest octane unleaded my seller has. You don't need any more octane than what the factory says unless you have done motor work.(saves money). The technology in the combustion chambers these days allows for higher compression ratios on pump gas than the combustion chambers of the 1970s (remember those days :) )An old Suzuki two-valve 12.5:1 compression 1000cc superbike motor would only make one lap if that at Daytona before gernading if run on pump premium in those days.

I suggest you run right around the octane rating the factory reccomends.

Enough of me, now go ride your bike. :D

Originally posted by Hotler:

now go ride your bike. :D

OK, You don't have to twist my arm. :)

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