HarleyTechTalk

Technical Forums => Twin Cam => Topic started by: roadkingdresser on December 14, 2021, 06:11:12 AM

Title: Question for the engine builders
Post by: roadkingdresser on December 14, 2021, 06:11:12 AM
Going to freshen up the engine in my road king after the first of the year. 2010-stage IV 103.s/e 260 cams. Was thinking about a set of roller rockers. What size would I need, And is it worth the money or should I just stick with the stock? I really like the performance of the bike,but after 40k .I have noticed some difference in it.Turning 70 in feb.but I still like the throttle twisting. May need to find some older friends to ride with,these young guys and the 114's and whatever else they run starting to make me feel old.  :emoGroan:
Title: Re: Question for the engine builders
Post by: Barrett on December 14, 2021, 07:54:21 AM
First off, I'm Not an engine builder.
I don't think you need roller rockers just a better choice of cams.
Sometimes less is better.
Title: Re: Question for the engine builders
Post by: kd on December 14, 2021, 10:42:18 AM
 :agree:   Spend some time researching cams that will give you what you want for your riding style and spend the money on them instead.  That cost will likely include a tune also. 
Title: Re: Question for the engine builders
Post by: Hossamania on December 14, 2021, 10:45:14 AM
A well done 103 will keep up just fine with the 114s. Screw those young kids!
Title: Re: Question for the engine builders
Post by: rigidthumper on December 14, 2021, 10:57:27 AM
Do you have a sheet? The 103/stg4 kits I've seen were less than stellar...
Title: Re: Question for the engine builders
Post by: roadkingdresser on December 14, 2021, 01:36:20 PM
Don't really have anything from the harley shop except the bike and the old parts. And the paperwork for what was installed. I had the kit installed before I took possession of the bike new. Really never had any reason to have it re-tuned. It does have the race tuner on it.
Title: Re: Question for the engine builders
Post by: Hossamania on December 14, 2021, 02:10:22 PM
What is your plan for the refresh?
Title: Re: Question for the engine builders
Post by: roadkingdresser on December 14, 2021, 02:43:02 PM
Well I got a set of cylinders and piston kits. Got them bored,new camplate.baisley spring and plunger,cam bearings.new chains.new tensioners. got a set of smith bros. pushrods,hylift johnson lifters. Going to have the heads checked and whatever they need. Put a new high volume oil pump in the beginning of the year. Have everything on the bench. Got a bobber i'm building for a friend,but the painter has the frame and tins and he's holding me up.I want to get that thing done and out of the garage so I can concentrate on my own thing.
Title: Re: Question for the engine builders
Post by: Sycho01 on December 15, 2021, 07:52:42 AM
I would look into porting and polishing your cylinder heads. I did my own and just had someone else do the regrinding of the valves and seats. After the Dyno tune there was a nice seat of the pants difference. The engine sounded much more aggressive. You could really hear the cam and a better exhaust note.
Title: Re: Question for the engine builders
Post by: roadkingdresser on December 15, 2021, 08:08:41 AM
The heads are s/e heads, supposed to be ported/polished
Title: Re: Question for the engine builders
Post by: Hossamania on December 15, 2021, 10:23:42 AM
Quote from: roadkingdresser on December 15, 2021, 08:08:41 AMThe heads are s/e heads, supposed to be ported/polished

It's always nice to get another set of eyes on them to see if improvements can be made. A couple of the vendors here would probably know if they could be better without having to look at them, or if they are fine out of the box. For your needs they may be just fine.
One question to know is, what are you looking for in a final product? What is your riding style, two up heavy, single rider hot rod, just a back road cruiser? It's not about individual parts, it's about a package that works well for you.
An old saying that still holds true: Horsepower is in the heads, and horsepower costs.
Title: Re: Question for the engine builders
Post by: Hossamania on December 15, 2021, 10:26:58 AM
Quote from: roadkingdresser on December 14, 2021, 02:43:02 PMWell I got a set of cylinders and piston kits. Got them bored,new camplate.baisley spring and plunger,cam bearings.new chains.new tensioners. got a set of smith bros. pushrods,hylift johnson lifters. Going to have the heads checked and whatever they need. Put a new high volume oil pump in the beginning of the year. Have everything on the bench. Got a bobber i'm building for a friend,but the painter has the frame and tins and he's holding me up.I want to get that thing done and out of the garage so I can concentrate on my own thing.

What size cylinders and which Pistons?
Title: Re: Question for the engine builders
Post by: tdrglide on December 15, 2021, 01:05:01 PM
So you have new cylinders and pistons, cam plate, oil pump,ect. Your heads have 40k on a hot rod stage IV motor. I would at least have them reconditioned by a professional head porter. There are some good ones who post here. Roller rockers gain you nothing hp wise. Only needed usually for real high lift cams
You could be over cammed with the 260
Title: Re: Question for the engine builders
Post by: roadkingdresser on December 16, 2021, 02:33:01 PM
Going to have the heads checked out. not sure about a cam choice rite now,I really liked the way the bike performs. Had the cylinders bored .020 over with a set of harley s/e pistons 10:1. Most of my riding is in the mountains,twisties. Been on a couple trips with it,never had any complaints.Bike may go another 40k, but i got this stuff at a good price and it's just a thing I got on my mind and the next thing is to get started. Thanks for the replies, but you know how it is to get old and thinking at the same time!     :bf: 
Title: Re: Question for the engine builders
Post by: harpwrench on December 16, 2021, 03:12:35 PM
What heads and pistons do you have? I was thinking some of the earlier stage 4 kits had mva style heads.
Title: Re: Question for the engine builders
Post by: D-1 on December 16, 2021, 03:32:30 PM
Correct, the early St4 kits with the 260 cam had the 110 style head. I think the SE pistons for that are obsolete. The newer St4 kit had CNC ported stock heads and 259E cam.
Title: Re: Question for the engine builders
Post by: harpwrench on December 16, 2021, 04:15:09 PM
Screamin eagle still has 10.5 and 11:1 103 domed pistons for the mva/110 heads last I knew...a 10:1 piston intended for the stock chambers wouldn't be a good combo.
Title: Re: Question for the engine builders
Post by: roadkingdresser on December 17, 2021, 02:17:34 AM
The heads i have kit# 17071-08a and the pistons 22441-08b-.010. What can you tell me about the heads. Everything from harley is obsolete if it's a few yrs. old. All they want to do is sell new. A lot of the reason lots of shops are closing.
Title: Re: Question for the engine builders
Post by: HogMike on December 17, 2021, 04:38:12 AM
Quote from: roadkingdresser on December 17, 2021, 02:17:34 AMThe heads i have kit# 17071-08a and the pistons 22441-08b-.010. What can you tell me about the heads. Everything from harley is obsolete if it's a few yrs. old. All they want to do is sell new. A lot of the reason lots of shops are closing.

If you try a search on that part number I think there was a post a few years ago with details on those heads.
I had a bike with those heads in 2016 that had a loose rear exhaust guide IIRC
 :missed:
Title: Re: Question for the engine builders
Post by: roadkingdresser on December 17, 2021, 05:53:43 AM
Thanks,I did the search on those heads and I liked what ohio hd had to say about them. Haven't started to take this thing apart yet, But I will be in touch with ohio.

Title: Re: Question for the engine builders
Post by: rigidthumper on December 17, 2021, 07:10:46 AM
22141-08b pistons are a positive dome, shaped for the CVO/MVA 95cc chambers, advertised 10.5:1. (+15cc). When measured, yields between 10.35 and 10.5 depending on deck height. As installed, your correct CR is probably ~8.75:1. You can verify this with a CCP test-I would expect to see ~175-178#.

With new pistons, a zero deck, and a Cometic .030" head gasket, yield is 10.88:1 static, CCP 190-192#, which would make your correct CR 9.25:1.
Title: Re: Question for the engine builders
Post by: harpwrench on December 19, 2021, 08:21:44 AM
Instead of roller rockers I would put that money towards a set of S&s hp103 cams, new lifters (wfo Larry). The SE260 has way more exhaust lobe than a 103 needs, ex opening at 65 degrees is killing it and the 28 intake open isn't doing anything good either. Follow up with a proper tune, hopefully someone around there can do a nice job but you might need to pay for a powervision license.
Title: Re: Question for the engine builders
Post by: Yellow09SERG on December 27, 2021, 08:05:12 PM
Quote from: harpwrench on December 19, 2021, 08:21:44 AMInstead of roller rockers I would put that money towards a set of S&s hp103 cams, new lifters (wfo Larry). The SE260 has way more exhaust lobe than a 103 needs, ex opening at 65 degrees is killing it and the 28 intake open isn't doing anything good either. Follow up with a proper tune, hopefully someone around there can do a nice job but you might need to pay for a powervision license.
I would agree with the 260 killing it. Had it in a 110 bagger and it was a dog till you hit 4000 then it started working just in time to shift. Swapped cams to get back to an early 40 opening and got the motor back to a motor that ran in the rpm range that was useful