Related to my 124" build, there's NOTHING stopping me from starting the beast mechanically. ambient temperature is ~ 60F, oil temp (from gauge custom mounted into the oil filter housing) is 54F.


she WONT start. cranks slow, watching voltage drop to ~8.2-9.1V while cranking (too low for reliable spark), and RPMs aren't even registering on the gauge (S&S IST ignition, according to the manual, needs 2-300RPM to start)


at this point, here's what I've got.

S&S 124, 10.8:1 CR, with ACRs (working properly, not dropping out during cranking)
AllBalls 1.4kw starter, brand new
brand new 4awg battery and ground cables (haven't added any additional cables yet, just the battery to starter, battery to frame, and frame to starter cables)

and for battery: currently using a BatteriesPlus XT30L (same size/specs as harley, AGM, 400CCA)

was using my battery, questioned it, had it tested, and passed. still didnt trust it, and now using a buddies known-good battery out of his roadglide....



still WONT start. voltage drop is identical between my battery and his, cranking speed is the same.


the only thing I haven't been able to do yet is just flat out point a kerosene heater @ the bike and get the engine up to 100+ degrees


i'm lost. I'm out of things to troubleshoot/test. it seems my last ditch option is a bigger (probably lithium) battery.


S&S says this engine SHOULD start at this temperature, with a stock starter, and a good battery. if thats the case....what am I missing?

 

Do they plugs get wet from fuel?

 

yep. plugs wet with fuel, and no signs of ignition (@ 8.5v i wouldnt expect a spark, and the IST needs 200RPM for the crank sensor to work properly)


there's no cam sensor or plate in this engine. it gets its spark-trigger from a MAP sensor (to know where intake stroke happens) and crank position sensor.


as a note, if I pull the plug, she spins WAY faster (as to be expected), and I can get a good spark on the plugs holding them against the engine


also, 3 gallons of fresh 93 octane went in the tank yesterday (was completely drained before)

 

Voltage drop is most likely the cables, you need FAT cables to start that set up.

 

I thought about cables as well, but I've also tried jumping this, and again, no luck

by jumping, I mean cables from my truck (680cca battery) straight to the post on the starter itself.

i'm all ears for more ideas, but jumping it like that oughta "bypass" the possibility of battery cables.

 

Actually, I like your cables but going bigger may not be a bad idea. I would also like to test out the feasibility of adding a second grounding cable nowhere near the current location. Split the draw/drop-off?? What I mean by testing it out is this: we can run a cable 39.37 inches away from the present location and see what happens then. If it works then properly route the cable and hide it as best as possible. If not then nothing really lost. Right?

 

This a question more than an answer.
If your ACRs are working correctly, wouldnt the motor spin (almost) as well as with the plugs out? What is the cranking compression on the motor?

 

My 111 has 150psi cranking with the ACRs, 185 without.

 

If you jump your battery to the borrowed battery in the bike or even to the starter, anything improves?

I wonder if something with the new clutch and ring gear is binding.
https://www.google.com/#q=harley+pinion+ring+binding
Happen to check the ring/pinion air gap?
https://www.google.com/#q=harley+pin...g+gear+air+gap

 

as far as ring gear binding, I'm not sure. air gap? again, unsure...BUT the comp/chain/basket are original, so all of that stuff went back together basically the same as it came out.

I've tried with and without the inner primary installed....no difference (actually spent some more time tonight with the grinder, was having a little clearance issue with the bolts tightened on the outer primary, had to relieve the bottom of the outer primary where the derby cover bolts in.


battery doesn't have enough oomph to crank it with ACRs disconnected, so no idea on CCP there...but S&S advertises ~185-190 without / 155ish with ACRs)

Tom: i'd add extra grounds if I thought it'd make a difference, but I got no difference in cranking speed (and only a marginal boost on the voltage drop) with the truck hooked up on jumper cables