Yamaha Bolt XV950

[Ducked]

Originally Posted By: Robenstein
Originally Posted By: Ducked
Originally Posted By: Robenstein
Most fuel injection setups on bikes have knock sensors that retard the timing if it detects pre detonation.


Ain't no such thing.

You can have detonation, or you can have pre-ignition, or I suppose you could have both, but you can't have pre detonation

In principle, knock sensors only detect detonation, not pre-ignition, though there seems to be some argument about that.


Splitting hairs on terminology my friend. English is the second language I learned as a kid growing up around Germans. I guess I will just use the more colloquial "ping" and "Knock" from now on as to not offend you.


"Ping" and "knock" are fine. They both mean detonation.

 

[Torkenstein]

The manual for my 2017 Yamaha SCR950 (same motor as Bolt) says do NOT use an engine oil with the diesel specification of "CD" without any explanation. The only reason I can imagine is concern about sensitivity of the O2 sensor / catalyst to oil additives necessary for the CD rating?

 

[Robenstein]

Well that is probably because some CD rated oils were for 2 stroke engines under the CDII rating. Probably a safeguard against someone using a two stroke oil in their bike that would cause engine damage in a four stroke.

If you look at the earlier CI4 and CI4+ oils you will see the zddp levels are high and if catalyst poisoning was the issue, they would ban those as well.

My old carbed non cat Yamaha had the same ban on CD rated oils.