The old flasher relays show the wattage of bulbs that they should be used in conjunction with. However, some indicator bulbs that I have (originating, I think, from the US) show 32CP. What does 32CP equate to in watts?

Thanks.

There is no conversion that I know of unless you have the manufacturers specs for the "efficiency" of the bulb.  (i.e. how many lumens per watt)

Bulbs used to be sold with a CP rating...  that changed to watts and lumens...  I used to have an old GE light bulb catalog that showed the CP and watts for different automotive bulbs.   Online catalogs sometimes show this too.  From what I remember, if you have the industry part number of the bulb...  say 1129...  you can usually find manufacturer specs.

For example, a 1129 (6v) shows a spec of 16.6 watts with an output of 265 lumens = 15.9 lumens/watt...  using an online calculator ( calculator.academy/watts-to-candlepower-calculator/ ) that comes out to a 21 CP bulb...  Which is the standard "candlepower" spec for the 6v Yamaha turn signals.

Do you know the bulb number or if they are 6v or 12v? 
A 12v 1156 turn signal bulb is rated at 27 watts with an output of 400 lumens = 14.8 lumens/watt which is right at 32 CP according to the calculator.

I don't remember the various 6v bulb variations but 12v often has several options in bulbs that look the same but have different wattages...  like a 1073, 1141, and 1156.  From memory the 1156 is the highest output of the 3 and the other two look identical but are lower wattage and light output. 

 

Thanks Mark.

I did a little online research before posting the question, but realised that I didn't have enough info/intelligence (delete as appropriate!) to come to any conclusion.

The 12v bulbs that came fitted to the various indicators that I acquired were 21w, 23w, 27w and 32CP. I haven't sorted the 6v ones yet, although I don't have as many of those to go through.

My best guess is the both the 27w and 32CP 12v bulbs are "1156"

They made a lot of 12v variations with different wattages...  you had to be a little careful sometimes...  a fixture designed for a 1073 bulb will accept the much brighter 1156 that looks exactly the same.  But the 1073 is much lower wattage and doesn't get nearly as hot.  The 1073 light fixture might melt if you used the 1156 bulb!  (Don't ask me how I know!)

The three I mentioned 1073, 1141, and 1156 are the ones we commonly used in the trucks.  There was something like 10 watts difference between them...  so if the 1156 was 27 watts the 1141 would be around 17 watts and the 1073 was around 7 watts.