I have a 2008 E.G. Classic with a stock 96", no engine work except for S.E. 255 cams; it also has the stock header with Sampson slip-ons, V&H VO2 Naked air intake, and it was dyno'd at the local H.D. dealer with a SESPT tuner. This bike now has over 91,000 miles, and last year with about 79,500 miles it started cutting out any time it was put under a load like going uphill or trying to pass someone, I'd give it throttle but it wouldn't go no where, in fact it would loose speed, it didn't cough or back fire, but it didn't have any power and would struggle to get to 80 MPH, and this would only happen at those hwy. speeds of 70 to 80 MPH, I never noticed it riding back roads 45 to 65 MPH. I took it to a local INDY as it's no longer under warranty, the INDY said I had a defective ignition switch, he replaced it, he also changed the in-tank fuel filter, checked all fuel hoses, and he also routed the breather externally instead into the intake. After that it did great for a while, but that was a little over a year or 12,000 miles ago.
Last week I rode it down to Daytona for Biketoberfest and as I got closer to Fla. I noticed it started doing it again, it would struggle to get to 80 and this time I noticed the exhaust got a lot louder when it did that. I got off I-75, took back roads the rest of the way, made it OK, and on the return trip I got back on I-75 and this time it didn't cut out as bad but it would still struggle uphill or to maintain a high speed, and it seemed like it ran hotter, but I made it home.
With over 91,000 miles I'm thinking it's time for a motor upgrade, I'd love to get a 2009+ bike, but with this mileage I'd have to give it away nearly, and a newer bike is not in the budget right now as I took a pay cut late last year. H.D. has a Long-Block program, but only the dealer is authorized to do the labor on this, the good thing is you keep your OEM engine VIN number. The INDY could do a 103 kit and some headwork, but I'm afraid of wear on the bottom end due to mileage. I see low mileage used 103"s all the time for around $2,000. to $2,600. which the INDY can install, but that would give me a different engine VIN number which might cause an issue as I travel a lot. I'll listen to some suggestions before deciding how to move forward.

 

I don't think ya have an engine/mechanical problem. Sounds like timing?? My guess is sensor/ecm trouble, but ya really need to find a good troubleshooting guy.

 

I agree with Oldhippie. Eliminate the stuff outside the motor. I've seen HDs with that kind of miles still running strong.


Also checking Leakdown, Compression, Sumping will give an indication of internal issues. Checking Crank Run-out (more $) will let you know if repairs are cost effective to you vs a takeout motor.


The takeouts are the cost effective way to go if you have issues in the bottom end (if the takeouts will bolt right in?) 'Never seen, nor heard of any issues with VIN#s unless they were running a chop shop...

 

It's kind of interesting that after the previous service you ran well for 12,000 miles. Might be interested to do the same stuff again and see what happens. Maybe it's as simple as your filter again.

I wouldn't jump into the engine, until you know the root cause of the problem.

 

Don't know if '08 has O2 sensors, but if so, that's where I'd start.

 

Is your bike using oil? What is your mpg like? Have you been good about oil changes etc? I would have the engine checked out (compression test etc) and see how the engine is doing. If the engine has been cared for it should have a lot of life left in it. It sounds like something else is causing problems.

 

Is your bike using oil? What is your mpg like? Have you been good about oil changes etc? I would have the engine checked out (compression test etc) and see how the engine is doing. If the engine has been cared for it should have a lot of life left in it. It sounds like something else is causing problems.
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2015 Road Glide Special Denim Black


Going to Daytona last week the bike was loaded up pretty good with all the camping gear, cooler on a hitch cargo rack, chair, clothes etc., plus I'm a pretty big guy at over 300 pounds, and it averaged around 38 MPG, and the round trip there and back, plus riding around the area was about 1,078 miles, and when I arrived back home and checked it the next day it had only used about 1/4 quart of oil. I use 20W50 DINO oil(non-synthetic) because it's quieter than when I tried using synthetic, and I change it every 3,000 to 4,000 miles, not every 5,000 like some do. Every other oil change I change the other 2 holes, BelRay 85W140 Big-Twin Tranny oil in the tranny, 20W50 dino in the primary, and I adjust the clutch once a year, usually around the beginning of riding season late Feb. or early March, and I also check my tires and brakes at this time.