For my 96" to 103" build I purchased the SE 50 mm TB, which comes with 4.9 g/sec injectors. Is this too much injector? The engine is very difficult to start and the current theory is the mixture is too rich to ignite when cranking. I still have the old 3.91 injectors, and I see H-D also sells 4.3 ones.

 

3.9 will be good for around 100 hp. The 4.9's around 125. The problem with too big of an injector is they are harder to tune down low because they are non-linear at small pulse widths. You may ask for less fuel and get more and vice versa. Any good tuning device should be able to cure your cranking fuel issue.

 

Thanks for the reply. The bike has a Thundermax, and is extremley difficult to start cold, forget hot. At first I thought the ACRs were not opening during cranking, but they are. I am running out of ideas, and TMax experts are in short supply. With my build (10.2 compression, 777 cams) it should be over 100 HP, so old injectors are probably not worth swapping out. Damn frustrating

 

If it were me, I'd dump the TMax, and get a TTS Mastertune. Then, I'd either try to v-tune it myself, or take it to a pro to make sure that it's dialed in.