107ci TW6-6 cams

[Tre_11 FLHX]

I am in the process of putting together another build and would like some input on whats been done with the above.  Bike is an 09 FLHX, TB is at HPI for 54mm boring and new Blade.  Plan is to bore stock jugs and use CP pistons- .030 HG, streetport heads and cc to Plan is to get the jugs bored to match pistons form Steve at GMR, also plan to have the heads done by him. I currently run a tw6-6, 103ci in my personal bike and I have it set at 10.3:1 with CCR at 194+. Using a TTS to tune and the bike is strong just off of idle, very pleased with the build!  Those with experience with the 107ci and tw6-6 cams, please share your recommendations to the following questions.

1. What compression should I shoot for/  heads cc'd and cut to what ?
2.  Expected Hp/torque- (stock headpipe, VH monster oval slip-ons)

It appears that (by using Bigboys calculator) with the heads set at 85cc flat top SE pistons (no entry available for CP) and an .030 HG the Static compression would be 10.44:1, corrected to 9.61:1 and Cold cranking at 197. Seems on the edge to me...thoughts? With an .040 HG it gives me 10.24:1.

As always I appreciate an insights!!

Regards,
Mike

[Hillside Motorcycle]

We've been there on several occasions.
What does your builder say???

[Tre_11 FLHX]

Hillside- I am doing the build-was looking for advice from those who have been there. Care to share what your experience is?

Steve at GMR is doing the jugs and he mentioned yesterday that he sets this up at 9.9:1, altitude and gas reasons.  Just curious what others are doing?

Mike

[Scramjet]

Mike,

Steve just finished one of those builds last night (but with headwork).  He got excellent results.  Talk to Steve.

I do not have experience with that cam but my experience with that compression is that you are close but OK on CCP.  One 107" build I ride and wrench with is around 196 CCP with no ping or stater problems at 600 feet altitude (HQ build).  My last 103 build (H-D) at 200 CCP had some starter problems on hot restart.  I would have liked compression releases but not less compression.

I can't tell you about my new 107" build yet (as you saw in my other thread).  I hope to run it on the street tonight for the first time.  It should finally go above freezing here today.

B

[Deye76]

Stick with .030hg. Have Steve sink the valves a little.

[HD/Wrench]

 If there was time on this build ( there is not one more to build just like it with a different exhaust owners coming from Utah on Sat) to add a larger t/b I know we could bump the hp. I can post up both sheets once I am done with the other. Made a bit more power than the 103 with the 54 cam. Rinhart pipe ( not happy with tq curve head pipe is a bit larger for a smaller engine) nice overall power in the end.

As for compression we feel with the gas quality not getting any better than you are much safer backing off on the compression a bit.  You still make good power and the engine is easy going, not picky about fuel. I cannot tell you how many engines we have fixed where another shop made a claim on what they set compression at ( was not even close to that , in fact much higher) , and BS  uncorrected hp/tq claims, owner gets the final product only to be extremely unhappy.   So if the bike is going to stay in one area , fuel is 93 octane , yes you can push the compression up a bit.  Other wise why bother, do the build and ride it.


Cant ride the dyno sheet down the road, 

This last bike is very close to what you are working with, stock head pipes, and bub 7 slip on's I will let you know what is makes at a true 9.9.1 compression, with a SAE dyno sheet. From there you can make your own choice. 

[Don D]

Regarding the heads and cam choice
No need to do too much to them with that cam. Compression will be right with flatops and a 85cc chamber. I am not sure the TB is going to have much of an influence but can't hurt. If you go with the larger head packages then would be looking at the TW7 which I have had good luck with when the valve spring pressure is conservative, quiet.

[HD/Wrench]

Regarding the heads and cam choice
No need to do too much to them with that cam. Compression will be right with flatops and a 85cc chamber. I am not sure the TB is going to have much of an influence but can't hurt. If you go with the larger head packages then would be looking at the TW7 which I have had good luck with when the valve spring pressure is conservative, quiet.

The 7 huh?? Would like to see how you fared with it,... I am not overly impressed with that cam in the  low 100 CI engines.  Have looked at it on many other builds and IMHO use the 6 or step up to the 8 in the woods line up. If you want that in between than buy the andrews 54. Money saved numbers very close if not better.  I just looked at a dyno Doc did he even posted in uncorrected that set up was ok but power wise we did better with the 6 cam in both hp and tq in SAE. Always open to see other combos that work.

I hope to have this other done as far as the dyno today. Just getting the engine buttoned up.

This is is as follows.

107 GMR
CNC heads 1.9/ 1.625
Compression 9.9.1
Stock T/B
SE A/C
Rinehart 2-1 pipe
Woods tw6-6
TTS tuner.

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[Don D]

They are your heads you know what works with your combinations
This is about combinations really not about cams alone.
You can work out what works best for the customer with your parts.

[Bagger]

Attached are cams I'm considering for a 106.5" build (Bore 3.937" X Stroke 4.375") in my 2002 Road King with 3.37 gearing.
I'm opposite of the majority of posters on forums.  For my weight and riding preferences, I want as much TQ as possible from 2000 - 4500 rpms (50 - 100 mph).
My modest goal is to achieve above 100 ft lbs TQ at 2500 (SAE 5th gear dyno run) within a corrected compression ratio of no more than 9.3:1.

MPH    3.15     3.37     Difference
5th       RPM     RPM    RPM
45        1907    2042    135
50        2119    2268    149
55        2331    2495    164
60        2543    2722    179
65        2755    2949    194
70        2966    3176    210
75        3178    3403    225
80        3390    3630    240
85        3602    3857    255
90        3814    4084    270
95        4026    4310    284
100      4238    4537    299


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[HD/Wrench]

Well as of 10 minutes ago a basic 98 went to a 107 kit. ( junk crank) so money is very tight for this customer and we are going to use a tw60  chain drive cam at 10.4.1 with our street port heads. Stock valve size 06 SG. So in a week will have that one ready to go.

Don do you have a sheet of the tw7 with a stock type head sheet?? would like to see what we spoke about. Like I said always looking for other combos

[Don D]

Will have a 110 in a week or so.

[HD/Wrench]

   Stock head pipes on this 107  killed the power.   96 hp and 111 tq   But on the brite side  41/40 hp and tq increase over stock  So I am sure that he will love it.  HE HE his wifes bike is a better runner  

[Tre_11 FLHX]

All- thanks for the replies.  Steve I am send ing you a PM.

Mike