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[103RKyeehah]

Ok, guys, I bought an 03 SERK.  Previous owner dropped in a set of 257 cams, thunderheader 2-1 exhaust, pwr cmdr, and 6speed tranny.  Overall, I'm happy with the bike. Here's my problem, having jumped off an 88" RKC with no major motor upgrades, I'm not sure if I'm getting the most out of this thing.  I haven't dyno'd it yet.  Runs rough when motor's cold, lurches in 3rd at around 2k rpms, runs like a baoh in any gear from 3200rpms and up.  I was told the 257 cams were a little tall for cruising around 2500 to 3000rpms.  Im running 2450 at 72mph in 6th. 3100 in 5th and all I have to do is open her up and hold on.  Just not happy with the around town performance running between 2200 and 3200rpms.  Any suggestions?  Any way to tune this up w/o major work?  What about a different cam?  Thanks.

[Unbalanced]

103RK,

Some of the higher lift cams dont run that well down low like your seeing.   Do you know if any head work has been done to the bike yet?

Check for any leaks around the intake can do this yourself with brakeclean
Check for any exhaust leaks even minor ones around the heads / fitting areas
What I would do is have a compression test done.
Dyno the bike to be sure the Air Fuel is correct

After double checking the dyno and knowing what your compression is make decisions or ask then what some people here might suggest to you.

You have a few to many unknowns to make a good decision in my opinion until these questions are answered.  

[103RKyeehah]

Thanks, I haven't done any of that yet.  I am burning more oil than I like.  Some guy told me though, if you weren't burning a little, you weren't getting the most out of your motor.  Bike came from GA where temps run a bit warmer.  Could dynoing it work out some bugs?

[Unbalanced]

RK103 your going to burn some oil its just the way it is.   If your buring more than a quart before your 2500 miles services it is an issue and should be looked into.

What you have is a high lift cam it runs best balls to the wall upper end ie FAST.
Dynoing the bike may take care of some air fuel mixture problems / timing and can be done and may eliminate some of your issue.

Why i suggested the things I did is to be sure you dont have some other compounded problem that your not aware of and then you would be wasting your money getting a dyno tune done because when you finally found the leak it would change the way the motor runs.

My suggestion if all checks out A ok and you still dont like the way the bike is running is to either try the 251 cam I had it in my 103 that built up from 88 to 95 to 103 and i loved it and ran it with a baker six speed or to go to a gear drive cam such as the 55g from andrews, but still you need to know your compression rates to decide what cam will work best if you are unhappy with the one you have.   You do not want to put a fast closing cam that runs from lets say 9.5 to 10.2 compression and you have 10.5 to 1 compression it will detonate and ping like a bear on you.    

I still stand on my initial recommendations to you before you go blowing money that maybe wasted.

[BLM777]

Got to agree with "Unbalanced" on the 251 cam.

[103RKyeehah]

UnBal, thanks for your suggestions.  Sounds like I have some work ahead of me to fine tune this thing.  I hope to get this to a local speed shop and have them dyno it soon.  What can you tell me about burning oil.  I've put just over 2200 miles on the bike since I bought it and have added about 2.5 quarts of Syn3 to it.  I have no obvious leaks on the outside.  What else should I be looking for?  Thanks

[DCFIREMANN]

I think you do have a problem and it might be in the cylinders. I would do a leak down test of the motor along with a compression test. This will tell you if you have a problem in the cylinders or not. I would pull those cams out of that bike and install a gear driven set of cams. You may have a problem with your power comander that may have caused you to have problems else where IE lean mixture. Do a few simple tests before you go into some major work unless that is what you have in mind already.

Be Safe

THE DAWG

[Unbalanced]

I have a question for you before you read below who did the oil change prior to you having this last one done.   You do know you will need to put in more than 4 quarts of oil right a lot of people do not do this when they have the oil cooler on the bike.   People forget its up there and automatically short you some oil and a lot of the guys run these bikes a bit short to begin with due to overfilling when the oil is cold.   Just something to consider.  Mine is good around 4.5 quarts in that area.   Not saying its the answer but if someone put in 3.5 quarts to be safe and then shorted you some by forgetting your oil cooler that is a quart right there and then if you ride hard you might be within the variances of how much oil is ok to  burn off.   just a thought before you read on.

If you have lost 2.5 quarts in 2500 miles Harley will consider that a problem anything over 1.5 quarts they start to monitor it and then decide how to act it may take you 5k miles once they get involved to warranty it, so I would not jump right in and change the cams.

[GC_Super]

103 RK, I noticed a couple of things in your post. First, your coming of a basically stock 88" motor, which has a lot more torque than a high cammed stroker, and you mention lurching at 2K rpm in 3rd gear. That's lugging the engine and will do damage to the lower end eventually. I think your adjusting to the different motor and need more time to learn how it operates. Granted, the 257 is not a low torque cam, but if you ride it differently, ie;  higher rpms, you might like it a lot more. JMHO, and it's cheaper than a cam swap. Also, a primary chain adjuster like the M6, HB 125 or now HD has one, will eliminate some of that low rpm lurching.  [smiley=xyxthumbs.gif]
Bottom line is that motor was not set up to your particular riding habits.

[Crawdaddy]

Unbalanced is right on.  But I think you could achieve the same performance with the 251 cam if you port the heads and increase the valve size.  The cam is allowing more mixture into the cylinder by lifting the valves higher.  Larger diameter valves can do the same without the vibration.  My partner has a 88 with the 95 upgrade and has the same complaint at 2500 RPM.  Unless he stays in lower gears and runs at 3200 to 3500, he shakes like a naked eskimo.  

Crawdaddy

[Twolanerider]

Unless he stays in lower gears and runs at 3200 to 3500, he shakes like a naked eskimo.

[103RKyeehah]

Thanks for all the advice guys.  I just dropped it off at a local and trusted speed and custom shop.  They'll be running a series of tests to determine where I'm losing oil and possibly compression.  They'll also run a series of dyno runs to fine tune it once any underlying problems are found.  Should be running great when they're done.

I'm getting used to the difference btwn my old 88 and new 103.  Not sure how long I want to cruise around at 3200 and up though.  Switching to the 55g or 251 is something I'm seriously considering.

I've learned to really appreciate what this current setup can do though.  Had her out on the highway for a while today.  Yee haah, she like to run fast.  Got goin' through the gears (btw, no rev limiter at 6100rpms, Unbalanced) and up to cruising aroung 3200 in 5th.  (that's about 80mph).  Just opened her up to triple digits and the power never went away.   [smiley=huepfenjump3.gif]

So if you like the top end and don't mind losing the mid-range, I might have a set of 257s for sale.  
Thanks for all your input.  This is a great forum. [smiley=xyxthumbs.gif]

[Unbalanced]

Sounds like you had a great day.   Hope the prognosis is just as good.   Keep in touch and let me know what they find and you decide to do.

[103RKyeehah]

OK guys, I've had my first check up at the local speed shop I mentioned before.  Didn't get to the oil buring problem yet, but did address the driveability of the bike.  After serveral hours on the dyno and several adjustments to the PC, the bike is running better than before.  Found out it was tuned too lean and that was causing the sputtering at low RPMs and when engin was cold.  Richened it up a bit and things seem much smoother.

Next visit will be to address the oil burning.  Still need to drive it a while to verify consumption is the same.  

I've got a few new questions for the group based on what I've learned so far.  1. Gear compensator- changing out the front pulley to get the torque into the lower RPMS?  2. Front plug white, rear plug black (after recent changes)??  

Oh yeah, you probably want to know the numbers from the dyno.  Nothing really impressive: 116 FP tq and 98 HP. After a very steady arch, both peaked out around 95 MPH which translates to about 4200 RPMs.  

Local guy, been building motors for years, says headwork in in my future and says my TH exhaust is providing  a bit more back pressure than I need for how I ride.

OK sorry for the book, but I could use some input to keep things in perspective.  Thanks

[GC_Super]

116 tq sounds pretty good. Unless you have a huge dip down low, those numbers aren't that bad.  Kinda suprised the 257 produced a lot more tq than hp.  Looks like if you get it all tuned up right, you might be happy.  Oh what did I say?  A harley rider happy without looking for more?  LOL   [smiley=xyxthumbs.gif]

[Unbalanced]

Mark after our conversation I would definately not recommend the compensator sprocket.  
there is no need to do this unless you have considereed strongly a 6 speed.   You need to address the issues with the front lean rear to rich.   This is not doable with the power commander since it tunes both at the same time.   I also dont recommend those dual fire spark plugs.  

I would check for exhaust and fuel injection leaks before next steps.

If no leaks are found then I would then look at the injectors to be sure they are both firing and spraying the correct patterns.

Now if they are you will probably need either a download or to buy the race tuner.   In this case I would lean more to the race tuner so that you can play with each cylinder provided you have a tuner that will work on your bike without the muffler on.   Since you have a 2 into 1 your going to need to get into each header and sniff to be sure they have equaled out and neither is running to rich or to lean.

I would take the money he wants you to spend on a sprocket 250 and spend it on an appropriate cam like a 251 or a gear drive that better suits the way you want to drive the bike.

I think your first order of business is getting the cyclinders to both run correctly and then go from there.   Moving on without taking care of this just means throwing money at a problem and still having the problem.

[syclone]

The SE 257 cams want at least 10.0 compression...better yet around 10.5:1 to give any kind of low end torque as well as perform as they should up top. One look in the H-d SE catalogue for the various builds and you will see the Stage 4 torque build...using 95" Se forged pistons and SE performance heads for a 10.5:1 comp ratio. with the 257 cams.
Our 103 motors are advertized as only 9.0 :1 comp ratio but if you do a hot compression test on one you end up with 165 lbs cranking compression which works out to @ 8.7 static ratio. That

[103RKyeehah]

syclone, thanks for your input.  I've learned through this process that whoever put the 257 cams in this bike  (previous owner) did so without completing the job.  My guess is he dropped 'em in, tuned it to run and then rode it hard from.  There is also evidence the factory recommended 'break-in' period was not followed.  In any case, I'm not happy with the 257s and definitely want to swap them out for something else.

FYI, the guys at Twin Visions Speed an Custom have been very forthwright with the options I have.  I haven't disclosed 100% of our discussions, but can tell you they have been very up front with me.  He did tell me in order for the 257 to work well with my bike, headwork and all that you mentioned would need to be done.

That being said, I need to budget for the future mods that need to be done.  I'm ready to consider one of the other cams mentioned, a race tuner, and possibly some head work.  I'm not made of money though, and want to do things right as I can afford to.

Can you tell me the major difference between the tw5 and 37g, and 26g.  I'm just getting used to the idea of changing cams and want to make the right choice.

Thanks

[grc]

Next visit will be to address the oil burning.

[syclone]

syclone, thanks for your input.

[103RKyeehah]

Question:  is the rear plug wet & black, or dry fluffy black?  Anytime folks mention oil consumption and a black plug, I suspect intake valve stem seal leakage.  This has been a large problem for H-D, and they in fact redesigned the valve stem seals for '06.  Just a thought.

Jerry

grc, rear plug was shiny, not soaking wet, and black.  Ring replacement has been mentioned by shop to resolve oil consumption.  

Thanks

[sefatboyscott]

Granted that as far as mechanics and modifications go I have no clue. One thing I do have a clue about is being a consumer. Hopefully if I was you and had purchased this bike from a H-D dealer I would have taken the extended warranty. That being the case I would take the bike to my local H-D ( read authorized ) wrench , tell them my problems have them replace the rings, fix whatever else is wrong and put in a brand new stock cam set up re tune the thing and leave with a bike that runs new again for 50 bucks...but thats just me. If there is damage to the rings there could be damage to other parts of the bike including the cylinder walls etc.. [smiley=sauer055.gif]

Now I know alot of guys know their chit when it comes to modifications on these bikes that make them go faster so on and so forth. It also makes sense to me that the epa could have alot of involvement on how the factory can legally produce their motors.............On the other hand however these other facts are obvious to me as well......The H-D research and developement team has paid more money than most of us will ever have using teams of scientist/engineers and state of the art equipment to produce what they think is the best possible set up for this motorcycle including all things such as tire size in real world driving conditions. That being said now I factor in whom I trust....H-D been making good bikes since 1903 and have built more bikes than anyone in these posts......( Ok we can take away a few years for AMF we all know those sucked! ). BTW the 05SEFATBOY is voted cruiser of the year v-twin magazine july!   [smiley=2thumbsup.gif]

[103RKyeehah]

Doing more research on Cams.  Found this description on two Andrews Cams and need to better understand which might work.  Here are the descriptions for the EV 23 and 27

EV23:
Note: Must check coil bind, valve-to-valve clearance and valve-to-piston clearance.
EV23 GRIND CAM
[list bull-blueball]

• Bolt-in cam for heavier touring bikes and high-geared bikes with 65-tooth rear pulleys
  Crisp throttle response and strong pulling power from 1,500 to 6,000 rpm
  

EV27:
Note: Must check coil bind, valve-to-valve clearance and valve-to-piston clearance.
[list bull-blueball]

• EV27 GRIND CAM
  Bolt-in street cam with fast open and close ramps
  Similar timing to EV3, but designed to produce a very broad torque band
  Pulls from 1,500 to 6,000 rpm
  

I know there are lots of choices out there and I appreciate the conversations and educated opinions of everyone.

[grc]

I believe the "EV" cams are for evolution motors only.

[103RKyeehah]

Thanks, GRC.  
See, that's why I need the help from you guys.
[smiley=dunce2.gif] [smiley=nixweiss.gif]

Thanks

Alright, so where do I find descriptions for my 103?  I found those on an Ebay listing.

[grc]

Try this link to Andrews - they have listings for chain drive and gear drive cams.
http://www.andrewsproducts.com/motorcycle/index.htm

Jerry

[103_RK]

Unbalanced, I change my oil in my 03 SERK and only add 4 qts.  When I check the oil level between oil changes, I am never more than 1/3 qt low.  Isn't the oil cooler too low to drain during an oil change?  It appears that the extra oil in the coller is not changed unless there is a way to drain it.  I change my oil at 2500 mile intervals and currently use syn3.  I am thinkng about switching to Ammsoil but have not bothered yet.

[SPIDERMAN]

yeehah    headwork is definitely in your future- - -   my opinion, Dave Mackey is the best H-D head guy in the business,  at one point before the V-Rods started dominating TopFuel Bikes, Mackey had 7 of the top 10 AHDRA Top fuel riders running his heads. I believe you can find him online  Great thing about Dave, is that he will come to the phone and discuss with you where you're at, suggest a few things and go from there   He cuts his own cams too, profiles are similar to Leinweber without the steep shoulders

[Big Time]

Really curious too hear what you cam up with. If you think to 257s are bad, imagine the 260s that the idiot put in the seeg I just picked up. Can you say two stroke powerband!?

[103RKyeehah]

Really curious too hear what you cam up with. If you think to 257s are bad, imagine the 260s that the idiot put in the seeg I just picked up. Can you say two stroke powerband!?

Hey Big Time, Let me tell you how bad the 257s are for my riding style.  

I recently made a 1600 mile trip across PA to NYC and then up through the mountains of NY and back across the Southern Tier of NY to OH.  Over half the trip was spent in the 45-50mph range and the other half was OTR at about 72mph.  I was loaded with an additional 85 pounds of gear for cold weather and was using wind deflectors over the engine guards. (riding in 45-50 degree temps made the guards a must)

First, I had to spend all my OTR time in 5th gear (rather than 6th) because there was too much load in 6th at 72 mph.  Second, while my riding buddys were running in 5th gear cruising through the mountains, I had to ride in 4th because of the load again being too much at that lower speed.  

Now, on the other hand, while on the highway with my buddies, since my torque kicks in right around where I was crusing......all I had to do was open the throttle and hold on if I wanted to fly around someone.  All the way from 72mph to 110 or so, the power just kept on coming.

Bottom line IMHO, the 257 cam is totally wrong for how I ride my SERK.  Put a load on it and it's even worse.  I'm planning on swapping out for 251s (or a comparable geard drive cam)over the winter.

For now I'll just enjoy the memories I made with my friends and look forward to another ride in the spring.

Later

[Unbalanced]

103RKYeehah,

Take a look at the 26g and 37g cams from andrews if you ride 1 up then the 26 if you ride 2 up then the 37g.

[Big Time]

amen! I'm leaning in the direction of decking the heads and using the Andrews 37Gs. I had that cam but chain drive in my 99 big bore FLHT and loved the powerband with 10:1 comp.
How much do I take off the OEM 103 heads to get 10:1 with the Cometic .030 gasket?
30 or 40 thou?

[Unbalanced]

Bigtime,

I would suggest asking the guy changing the springs to double check your clearances and what is needed there.   It is going to depend on how much is in your heads despite them being factory I would still suggest them being looked at to know EXACTLY what can be removed and how many CC's are in the heads themselves.   The problem is after 10 to 1 if someone screws the pooch even a little bit you will get a lot of kickback to the starter and the relief for that is compression releases, if not installed initially they would need to remove the heads again to install them.

Another suggestion to you if you liked the 37g is to check out the 55g it runs exceptionally well up to 9.8 and 10.0 to 1 if your looking at stump pulling torque this might be another answer for you.   This cam is at the top of what your stock springs will handle since it has a 550 lift.

[sqrrl24]

103RKYeehah,

Take a look at the 26g and 37g cams from andrews if you ride 1 up then the 26 if you ride 2 up then the 37g.