Home Forums Road Racing Track Day Discussion Reply To: Track Day Discussion

Robert Lawson

OK, So Why???

This is the inevitable question….. and I have the answer.

First the Question: Why did the LRB check out well before its scheduled maintenance window?

Its a bit involved and goes back to the last time I ran it before buying the newer Homologation. You see, I stuck this engine at the April test in 2017…. I have posted the video here. It blew up when I ran it out of gas, it stuck so hard it cracked the cylinder at a mounting point which caused it to leak H2O externally from the water jacket. That cylinder had gone to the plater and back before finding that issue. This was the reasoning behind buying a newer engine…. the spare cylinder for this old engine was also in need of plating so the engine went on the bench. While playing with and testing the newer engine I sent out the spare and my A kit HRC cylinder for Rich to US Chrome for replating. I rebuilt this old spare with new clutch, reeds, plating and top end….. and there she sat until after MIS last year. Another mistake was using the air filter from the newer engine after that rod bearing was launched on this engine. I found debris embedded in the piston & head plus a broken reed after running it last Fall.

Now, to current day, I stuck this old engine at Grattan on Saturday morning. This was due to a lazy change made at Gingerman last fall, adjusting the needle instead of the main….. I leaned the entire throttle position curve (0 – 100% throttle) by dropping the needle all the way down AND¬†removing the washer that was under the clip. (2 full clip pos.+ washer = a full jet size)¬† If I had read my notes from Gingerman this would have jumped right out, I went through the carb but not the slide needle!

So we have a second seizure, a second lock-up and spin, on the same rod bearing. Then to add insult to injury (literally!) I run it to 14.900+ RPM’s when its back together and THAT is the answer to the question of “Why”.

A hard blow up, ingested shrapnel from a dirty air filter, a second blow up, and to top er off lets run the guts out of er!!!

Mother always said “Hindsight is 20/20”

I say, maybe not Mom’s…. cause I’d run it again if we were going tomorrow!

I’m working on tomorrow right now…..

Peace Y’all,