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Options For Bottom End Replacement-Twisted Crank 103"

Rod Stewart

Active Member
Bike is an '07 Road King with a Stage II 103" kit and SE 255 cams, done last year.
The right thing to do of course would have been to check the crank runout while doing the Stage II kit.
But that didn't happen, and just recently whilst getting some diagnostic work done at the local dealer they said they thought the engine seems to vibrate a little excessively.
Doesn't seem any different to me than when it was still a 96", but now I am concerned, especially after reading the thread about multiple twisted cranks with '07 and '08 bikes. I am leaning towards getting the runout checked (or checking it myself) just to see if there is any reason for concern.

So if it turns out that the runout is excessive, what are the options? Here is the way I see it:
1. Sell the bike immediately and run.
2. Pull the engine, disassemble and send the crank away for trueing and tig welding (like it should have been in the first place). Bore the case for 4.00" 110" cylinders at the same time. Cost: likely under $1000, if I do the R&R myself.
3. Crate shortblock assembly PN 16200070; ($1695) This would replace the entire bottom end with all new parts and is good for 96" and 103" builds. But who knows if the crank is any better than the original? I'd like to think it is the beefed up version introduced in '09 at least. And the case would not come machined for future 4.00" 110" cylinders, so it would be good to get that done before reassembly. Add more $. The nice thing about this option is it would be done fairly fast and includes most gaskets and would reuse the current cylinders, heads, cams etc.
4. SE pro crankcase PN 24601-10B ($700), plus either SE 4-3/8 crank ass'y PN 23729-07B ($730) or SE 4-5/8" crank ass'y PN23893-10A ($1250). Plus you still need all gaskets etc. The 4-3/8 crank will get you a 103", 110" or 113" engine; while the latter will get you a 109", 116", or 120" engine; depending on cylinder bores of 3.875", 4.00", or 4.060" respectively in each case. The crankcase comes already bored for anything up to 4.060". Lots of extras would be needed, and a fair bit of time.
5. Complete drop-in crate 110" motor PN 19176-16 ($5195). This would also be faster option, and I could sell the current 103" engine for maybe $2000. Net outlay $3200 plus R&R time.
6. Complete drop-in crate 120ST motor PN 19221-15 ($5695). For the minimal $500 difference over option 5 this would be cool, and I could still sell the current 103" engine for maybe $2000. Net outlay $3700 plus R&R time.
I am sure there are plenty of incidentals I have overlooked, but just trying to get the big picture.

So it is just a matter of time versus cost, versus what I want in the end.
If it was your decision, what would you do?
 
Option 5 and 6 would be great if your able to pre sale the original, they both have a warranty on them, top to bottom, no taking apart later for cylinder or head upgrade.
Do they have a core charge on them?
If this is the way you deciede, I would start to advertise the used motor now to see if you can find a buyer while it is in the bike so they can hear it run and take a test ride too
 
It's way too early to start thinking about a new engine, check the crank runout first. You may not have any issues and you'll have your piece of mind. If there is an issue with runout you then have options. JMHO.
 
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First things first. Check crank runout as Jeff suggests to verify that the excessive runout is causing the vibration; please check from the right side. Easy to do yourself and would take all of an hour.

'07 was the year for crank issues; new offshore supplier working out the quality bugs; most sorted out by '08. I would not consider any option except #2 with some changes. Out of pocket is going to be more than the other options simply because there is no cost recovery from selling the 103" but I don't think you can really count on that anyway. That motor will likely end up sitting in your garage and getting in the way for a long time; not much demand for a 103" motor with a twisted crank. Work with what you have. It is the only option that gets you to a bullet proof motor when completed.

I would suggest a couple of changes though. Rather than splitting the cases yourself, crate up the lower unit and send it to Hoban Brothers (AKA Darkhorse). Call and talk to John Dahmer and chat him up on the pros/cons of rebuilding your crank using their H-beam rods vis purchasing one of Hoban's worked SE cranks with H-beam rods; cost/benefit differences. The last one I had done ran about $1100 to true/balance/plug and weld the crank, Timken conversion and case boring. I sent the assembled lower unit, Hoban serviced it and returned, so all I had to deal with was the R&R. Hoban does not weld the cranks unless requested by the customer. They use an oversize crank pin and their "Pro Plug" but will weld at the customer's request. IIRC, shipping, out and back, ran just under $100 each way.

Additionally, have the left side crank bearing converted to the Timken setup and cases bored for 4.125" cylinders for a 117" configuration. If you feel like living on the wild side, have them replace the 4.375" crank with the 4.625" crank for about the same cost and you are sitting on a 124" motor. You will have to select cylinders and pistons before the crank and case work can be done. John will need to know pistons because there is the main case bore and the step bore; two dimensions they work with. Pistons are necessary because John must know weight of piston/pin/rings/clips to balance the crank.

As always, JMHO.
 
Something else to consider, how much money do you want to sink into a 9+ year old Road King?
Unless you can't live without it, using option 5 and 6 you'll be so deep into it you'll never recoup close to what you have spent. JMHO.
 
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Something else to consider, how much money do you want to sink into a 9+ year old Road King? Unless you can't live without it, using option 5 and 6 you'll be so deep into it you'll never recoup close to what you have spent. JMHO.

Jeff,
You are right to point out to Rod that he should be thinking in those terms; I do not disagree. However, Rod is already there having spent the $$ to go from 96" to 103" which may have (TBD) a motor that will put the new owner in the same position Rod now finds himself in; so now the question becomes one of degree. It would be an easy choice for me as was choosing option #2 for a couple of reasons:
1. I like working on the bike almost as much as riding it.
2. I would know that when done, the motor would be bullet proof which cannot be said for any other options.
3. I would know that I would probably dust of any other Harley that rolled up on me.

I have somewhere way more money sunk in a 2002 FLHT that I would ever get from a sale; I don't even want to go back and add it up because it is probably more than I think. However, in '08 I bought the bike as a "project" bike knowing that there would always be something I would be changing and that I would never sell the bike until I decided to quit riding. I was tempted once in 2010 when I test rode a new FLHX and FLSTC and, after the test rides, it was an easy choice to stick with the '02.
 
Jeff & dolt;
You guys are completely correct in your statements regarding recovery of costs. Not really a concern of mine and here's why.
This bike lives in AZ and only gets ridden for about 3 months in the winter when we are down here. The rest of the year it pretty much sits idle. It will never see more than 3-4 K miles a season.
It was bought used about 3 years ago and does not represent a big cash outlay. It is low mileage and already had a ton of extra chrome on it as well as Rinehart true duals etc. It is exactly what I wanted for a part time winter-down-south rider.
The Stage II kit was done last spring by my daughter (licensed auto tech) and myself under our carport in Florida, just for interest sake, with no particular timetable or other goal in mind, except to make it go faster. We are both quite mechanical and enjoy doing this kind of stuff. Part of this came about because the local dealer in Florida had the stage II 103 kit on sale for a price I could not pass up, like about 35% off MSRP.
Whatever way I go from here, do I care about recovering my costs? Frankly, no. When I make changes to something I do it because I want it that way, never mind resale. My bike; my decision.
Most of my riding is just simple cruising; I am not out to prove anything or race anyone. I'll leave that to the metric guys. I just want the peace of mind that I am going to get there and back, and with a certain amount of comfort and style.
I would likely only open her up fully about 2 or 3 times a season, but when I do, I want it to move out with some authority, especially when riding two up.
Don't get me wrong about costs; I like to see good value for the money I spend, on bikes and everything else. But if its something that makes monetary sense to me I'll go with it. That's my story and I am staying with it! ;) Hope it makes sense.
 
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