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**PRG** · 03-05-2020, 08:49 PM

Howdy sir,

I will only respond to one element of your post regarding baffles and leave the rest to the experts. I bought a matching a number 48 Chief in 94 along with a pile of spares to include the complete powerplant, primary and trans for a 69Xx 53 Chief. Then now understanding how late Indian Chiefs lubricate their motors using windage at the high cost of efficiency and ridiculous ring requirements I knocked the baffles out of my first day 48 production Chief and built a hot rod (though stock appearing) 80 inch Bonnie cammed and carb’d machine using all those parts to include that primary and comp sprocket. The only pistons on offer at the time using modern thin Mahle type gas expansion rings were Bonnie 74’s, which to keep the compression reasonable (by then young whippersnapper standards) I cc’d/clayed the heads and then cut the crowns for clearance. Designed for modern motors that run neutral or partial crankcase vacuum these rings do not like the back pressure of baffles there designed to act like a Venturi in a carb, breaking up oil stream and droplets into a mist to lube the timing chest. Knocking the baffles out and going to a more easily aerated 20/50 multi over the original 50-60wt has turned out to be the answer. A month ago, in an effort to lower my compression ratio I removed the standard .030 compressed fiber head gaskets to replace with .062 copper. After 25 years of riding u can still see the cross hatch in my cylinders that I plateau honed to a very fine RA. No wear to speak of, it’s here at Bike Week in Daytona now running as well as it did on its first trip in 97. No baffles required, use high zinc Valvoline VR1 20/50 race oil.

**Bubbalowe** · 03-05-2020, 10:33 PM

In agreement with Peter regarding the advancements in metallurgy and ring design negating any need for baffles. Curious what the argument is for their need today. Neutral / negative crankcase pressure ideally happens at cruising speeds around 50 mph, reason police bikes had the breather drilled for extended idle times to keep from slobbering oil. If baffles are such a good idea modern engine builders would still have them instead of piston cooling pipes.

**BluChief** · 03-05-2020, 11:32 PM

Thanks for the reply PRG and Bubbalowe

My understanding of the baffles if there are no baffles the front cylinder goes dry and the rear cylinder get flooded with oil.
Looking at Kiwi's catalog his new engines have "baffles to control top end over lubrication"
But I can understand the restriction and pressure problems the baffles can cause.
I know my S&S Evo has no baffles but there are more breathers to handle the pressure

Now to figure out if it's a good idea not to use 80" rods on an 80" engine, I think the older rods will fit but some are weaker ?

**tfburke3** · 03-06-2020, 09:21 AM

80 rods are beefed up compared to the 74 rods but fit the same.There are two versions of 74 rods.Earlier have small gusset at the wrist pin hole stronger later have no gusset visible because its all filled in.I would not use them and it would make me wonder about the stuff you cant see especially if it had to be pointed out by a third party and not the builder.
I wouldnt worry about baffles.I wouldnt remove good ones and I would not try to replace missing ones.
Starklite has Carillo clones.A compromise like the rods may work perfectly fine but its not worth it to skimp and then always wonder about your decision.
Tom

**tomfiii** · 03-06-2020, 02:16 PM

Indian Rods; https://www.starklite.com/indian-mot...fy-chief-rods/

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