The Infamous 75' Trick Start 850 (2010)

Keith,

The battery specs are:

Yuasa YTX20CH-BS
Sealed Construction
18 Amp-hours
270-300 CCA (rating varies with vendor)
11.4 lbs
Dimensions 6" x 3-7/16" x 6-3/8"

I had to slightly "adjust" the front lip of the cage to accept the battery. Other than that, it fits perfectly in its normal (vertical) attitude. You may want to consider a 3-phase alternator upgrade as well. On my Mk3, with all lights on and an EI, the system recharges at all engine speeds above 1800 rpm.

I bought the battery 18 months ago from Powersports, about 100 bucks with shipping. There may be others now with improved specs, but the dimensions on this one are the maximum that will fit without serious modification of the cage.

Thanks Rick -

I just checked the Yuasa site - it shows the batter rated at 270 CCA. http://www.yuasabatteries.com/battery.p ... 5&vID=3946

I already have the 3-phase alternator (Sparx) as well as the heavy-gauge cables.

Thanks again,

Keith

I did a mod on my starter some 2 years ago, below some pictures. Used the Harley housing with 4 brush holder, and fitted 2 needle bearings (the open end with a seal), as well as bronze trust washers. Together with some heavy leads, she starts like a dream so far. I have to wait and see how the shaft ends hold. Going to check this winter.











cheers, Bennie

slimslowslider said:

I did a mod on my starter some 2 years ago, below some pictures. Used the Harley housing with 4 brush holder, and fitted 2 needle bearings (the open end with a seal), as well as bronze trust washers. Together with some heavy leads, she starts like a dream so far. I have to wait and see how the shaft ends hold. Going to check this winter.

cheers, Bennie

Click to expand...

Bennie, How about a 12 year update on your Mk III Prestolite starter bearing mod?

Sorry Charlie, I missed your post.
Further to your PM questions:
The bearings are dutch INA types HK0912 on the closed end, and HK1712 on the open end.
No inner cages, they run straight on the armature shaft.
The seal is a regular 17/27/7. The bronze bush is shouldered to fit.
Have had the bike apart, as well as the starter, for many years, since about 2014, I ride the MK2.
No signs of wear to see, but that does not mean something as I rarely used the starter.
I am more a fan of the "feel" of kick-starting the bike.
Plus I was used to freeing the clutch with the kickstarter anyway.

All are possibilities but for the record : replacing the battery cables with oversize fine strand battery cables made the single most improvement!!!!