Head speed with TRM's 231

[Bobs]

What's the recommended head speed for the Spectra G (7.15 gear ratio) in both normal mode and Idle-up modes using the Stage 1 TRM 231 motor? Thanks.

[rbort]

I run mine at 1550 in normal, 1650 in idle up 1 and 1750 in idle up 2. The machine does very well at these rpms and I use the 1650 speed the most.

-=>Raja.

[Bobs]

Thanks, Raja. 1650 and 1750 are the same head speeds I run in my Intrepid but I thought maybe with the difference in gear ratios that the Spectra G head speeds might be different. So with the 231 I'll just be running more motor RPMs. Great. Thanks again.

[FelixGiant]

Hi,

I'm not an expert but I noticed that Raja has a G26 engine in his Spectra.
I have a Spectra with a Toxic TRM 231, 7:15 gear ratio, and I think a little higher head speed in idle up 2 is better, around 1800-1850 rpm.

Bobs, ask John Garst also, he has many hours on the Spectra.

Regards
Gianluca

[Bobs]

Thanks, Gianluca. I didn't know Raja was running a 260. That's what I have in my Bergen and I kinda thought the head speeds would be different. Maybe John will read this and chime in. I've read through the Spectra G Operator's Guide and did not see any recommendation for head speeds. However, I've done the math and with a 1650 head speed and 7.15 gear ratio the engine RPMs will be 11,797, that's around 1,200 RPMs more than my Bergen is running at 1650, so I thought maybe those numbers would be acceptable. Anyway, thanks for the info.

[FelixGiant]

Hi Bobs,

I have checked my TRM 231 instruction, they say that the motor is happy in the 12,250-13,500 rpm range, with 12,750-13,250 being the optimum 3D range.
This translate to 1,780-1,850 headspeed rpm range with a 7,15:1 ratio.

Regards
Gianluca

[bigrcr]

Felix has is correct! :D

[Bobs]

Thank you both. I kinda figured the numbers would be a little higher than my G26.