The India-made Iron Barrel engines have valve seats which can handle the unleaded fuel.
Now that this thread has been brought back up.....When I was at Performance Cycle a couple weeks ago getting my new gloves, I asked about octane booster verses mixing straight race fuel. Apparently all the racers, street and dirt, prefer to use the VP Racing Fuel. $60-$100 per 5gal can, but octane ratings are between 95-110. He also showed me an octane booster by PJ1 that said right on the front of the label "Contains Lead Substitute". He said this is what most guys were buying that weren't using race fuel and liked it.Scottie