Harley Davidson Compression Ratio And Cam Timing

A detailed video on compression ratio in reference to timing.

[@thomasborger6548]

An articulate gent who presented the lesson well.

[@nikolaiownz]

Massive respect for sharing knowledge and software I learn something in every video

[@asheraidan1392]

i know I am kind of off topic but do anybody know of a good place to stream newly released movies online ?

[@alejandroarmando8488]

@Asher Aidan I use flixzone. Just google for it =)

[@My45ToYourThroat]

Complete and thorough breakdown. Awesome job learned something new today.

[@michaelhenry550]

AWESOME explanation!!! The possibilities when you have the correct info to go with the small things we think we know how to properly do!!! AWESOME!!!!

[@ironhead9507]

you are an excellent instructor as well as engine guru. I'm saving up for a kit

[@shadyrack22]

Hey, just want to say this is a really great video, it is a great explanation and really helped me out. Thanks

[@zigzagzenith9409]

Thanks. Really helped clear up some confusion I had around compression ratio and cam selection

[@BMWHP2]

Hya Aaron, Good to see you still share your awesome knowledge with us. And thanks for all the good times with the Buell friends from all over the world. Grizz.

[@HAMMERPERFORMANCE]

Thanks Griz! Hope all is well in Nederland. If you get back to the US, look me up! You have a place to stay in beautiful Sandpoint Idaho. Oh, and check out this picture: www.aswracing.com/nederland.jpg

[@BMWHP2]

@@HAMMERPERFORMANCE Thanks mate, same goes for you two. When ever in Netherlands, your welcome to stay. And thanks for that picture, Awesome time.

[@fishandgameman]

Great video! I thought my understanding of camshafts was above average. Until now, I never figured in or understood compression with respect to intake valve closing or what I now understand as static and corrected compression ratio. This has been an epiphany for me. I considered air/fuel charge flow with respect to closing the exhaust valve later to take advantage of the lower cylinder pressure, before the piston begins pulling the charge into the cylinder, because of the exhaust pulse leaving the header. I began wondering how compression may affect performance with my cam selection. I’ll do my research now because I believe it does. I changed to a Woods WM8-22XE in a 2018, 107 M8, and in the process went to aftermarket cam plate, oil pump, lifters, cam chain tensioner, and pushrods. I thought I was happy until I removed a restriction in my factory head pipes, upstream from my TAB 4 1/2 slip-ons. I was absolutely amazed at the improved performance through the whole RPM range. At the same time I switched from the Zombie to the standard 2 1/2 inch baffles because it was too loud. I assure you it was not the baffle change that made the difference. I run the FP3 to manage everything. Before the restriction was removed it would simply stop taking throttle input past a certain point requiring a shift well before reaching a reasonable RPM. Now, the engine moves air like crazy with a very responsive throttle into higher RPM ranges. That got me thinking, with flow rate of the stock heads, I may be able to achieve performance gains simply by switching to a higher compression piston with increasing bore or stroke. What I take from this video, it can change performance. Also, I may already be near peak with the current set up since the replacement cam was probably ground for no restrictions. Aftermarket head pipes might bring additional gains with less turbulent flow or minor radius differences. I really appreciate this content and my understanding is much greater after viewing.

[@boatman19607]

Spoke with you on the phone and finally got my kit sorted out (my issue as I changed my mind on the heads). I had ordered the SE ported/ CNC heads then switched to buying used 2004 heads and having you port/polish for me. Originally got your 1275 big bore with flat pistons, then switched them out for the 30 degree ones to match the heads you just did for me. Can't wait to set it all up. This was an excellent video, thanks for the detailed explanation. You guys have excellent customer service, too bad you're on the wrong side of the Country I'd love to stop by :)

[@JamesHall-o9r]

Great job hammers, the question is what happens when you replace the oil pump gear with out the gear tool to keep it from moving and it did so next steps would be what

[@roncoburn7771]

I understand it all I love this stuff

[@georgeo138]

Thanks!

[@garycb8592]

Another good video lesson. Thanks for continuing to post.

[@ВасилийУткин-л4н]

Thanks for video!

[@trailerparkcryptoking5213]

Great content! I have a question concerning these calculators. If you don’t start building compression until the intake valve closes, then why enter the ABDC number @ 0.053” lift? The valve is still open! The flow at 0.053” lift is probably low, but the valve is not seated.....

[@stachethompson6530]

It's a wonder Harley doesn't incorporate variable cam timing. With a chain driven system, it seems like it would be a pretty easy addition. Maybe they have and it's just too pricey.

[@BobBob-fp5fn]

In your opinion, what is the ideal compression that produces the most power for 91 octane?

[@HAMMERPERFORMANCE]

210ish psi is a manageable, IF everything is set up right. By that I mean you've got reasonable squish band surface area (20% or more of the bore area), a squish clearance under .040", a good ignition with an appropriate map or curve, your fueling is correct, your spark plugs are the correct heat range, your exhaust doesn't revert, the bike isn't geared too tall or pulling a heavy load, the motor's heat is under control, etc.

[@BobBob-fp5fn]

Thanks

[@jackassman6726]

Great info Thank You for that ,,, Hammer is going on My Bike when I need to rebuild My Engine ...!!!!!

[@b.j.photoart3424]

hi, i just tried this because i'm going to install wiseco 10.1 pistons in my evo. I was looking for a woods w6 and andrews ev27 cam...woods gives 9.82 cr and 213psi while the andrews gives 9.98cr and 217psi...so I think the andrews is better? it is an fuel injected bike

[@CarlosGarcia-ls4hn]

Ok., we are now in 2021, but let me ask this...I tried to follow your comments...but I am still trying to decipher this. I want to get rid of my SE266 cam in my 2000 Springer and go back to stock. My motorcycle is high compression and has compression releases. You will most likely ask, well what is the cylinder compression, and/or ratio? Well, I have no idea to either one. How important is that for me to know? So then, even if my engine has high compression, what damage would be caused by returning to the OEM cams?

[@Manis-World]

It will feel like it wants to run like an animal if it’s runs but will detonate like crazy and live a very short life it any at all

[@Kenevoslcomp777]

Miss my sportster with my hammer kit too bad it stopped working after 3 years but pulls hard from beginning to end with just stage one and big bore kit Have a dyna with stage 3 that feels so slow compared to my sportster with the hammer kit

[@jayscorner5387]

I'm thinking of doing the 120HP kit for 1200cc 2016 72, at about 5k miles. Will it still be streetable and usable or do you not recommend that kit for a street, non-track exclusive bike. I know the question is not directly related but this is a fairly new video and I am hopeful for a reply. Thank you for the information.

[@HAMMERPERFORMANCE]

We put a lot of work into engineering the 120+ package to be a real-world, pump gas friendly setup with excellent reliability and longevity. It's not a race motor package at all. Read more about it here: www.hammerperf.com/883conversions.shtml#120hp

[@steveruby523]

What psi should a stage 1 103 run

[@dickhammerbush9630]

I had cams and adjustable pushrods installed on my 04 sportster and I’m now having valves hitting pistons and bending all 4 valves, any idea what the reason is?

[@HAMMERPERFORMANCE]

An 883 I presume? 883 heads have longer valves to reach their shallower chambers. This puts the valves closer to the pistons to start with, as compared to 1200 heads. So cams that are bolt-in for a 1200 are not necessarily bolt-in for an 883. The operative cam specs are the "TDC Lift" figures. That's how far the valves are open as the piston passes through TDC between the exhaust and intake strokes, when both valves are hanging open. So high TDC lifts is what gets you in trouble with piston to valve clearance. Anytime you run cams with a "TDC Lift" (see the spec sheet) greater than about .200 on either valve, you're taking a chance of valve to piston contact. Watch this video for more information on this: kzbin.info/www/bejne/nJ3KlYyKeMuLq7c

[@dickhammerbush9630]

@@HAMMERPERFORMANCE yes it is an 883 head. So what are the biggest cams I can use? I was given the fueling 505/515 cams and that’s what is installed at the moment

[@HAMMERPERFORMANCE]

@@dickhammerbush9630 Feuling 505/515's have very low TDC lifts of .137 intake and .150 exhaust. These are not big enough numbers to cause piston to valve clearance problems, even with 883 heads. Therefore, disregard what I said earlier, something else must be going on. If it was mine, I'd verify the cam timing. First and foremost, make sure the marks are lined up properly. The mark on the pinion gear should be positioned such that it's pointing straight toward the middle of the #2 cam. If it's pointed even a little bit off to one side, it'll make all the other marks misalign, you need to point it right toward the middle of cam #2, and obviously it's mark needs to be aligned as well. If all the marks look good, then you can do a TDC lift check. We have a tech article that explains how to do this here: www.hammerperf.com/ttspotcheckcamtiming.shtml . It's a bit tedious, but it's a whole lot simpler than rigging up degree wheels and dial indicators, and it'll tell you right away if something is a tooth off. Some people mistakenly believe that pushrod length affects lift. But a hydraulic lifter is self-adjusting. To the extent the pushrod is too short, the lifter automatically lengthens itself, and the extent the pushrod is too long, the lifter automatically shortens itself. So long as the preload is in the lifter's self-adjusting range, you're golden. And if you're outside that range on the too-long side, the motor won't run, because the valves won't close and therefore you won't have compression. If you suspect an issue there, run a compression check, it'll tell you in a heartbeat if valves are failing to close.

[@tonyking2030]

What an interest video….thank you ✅👍😊

[@kermets]

Hi, can the program be used or changed to show dynamic compression ratio ? cheers Brett

[@HAMMERPERFORMANCE]

It already does. We just prefer the term "corrected compression ratio", to avoid confusion (guess it didn't work this time). The problem with the term "dynamic compression ratio" is that it can also mean compression ratio with consideration for cylinder fill (generally expressed as "volumetric efficiency or VE). Only real motor nerds use it that way, but a few people do. So to avoid confusion, we use the term "corrected compression ratio".

[@kermets]

@@HAMMERPERFORMANCE Great thanks, why is the cam degrees @.053 ? if we used software for another engine say a SBC would .003 " make much a change, could it be changed or "add a other" box to program.

[@HAMMERPERFORMANCE]

@@kermets Man, I have no idea why the Harley world uses .053 and the automotive world uses .050. That's one of life's great mysteries to me. But it's a pretty negligible difference.

[@goodboyringo9716]

Don't forget to tell KZbin and your customers this download is NOT supported for Apple macOS users and can't be downloaded Only supported for windows!!

[@HAMMERPERFORMANCE]

Tell you what, you get double your money back ;)

[@goodboyringo9716]

@@HAMMERPERFORMANCE ....Thank you very much for nothing ! What a great joke ! It's been 4 years now and you still having helped the Mac os users with this problem. Being a great company as you are but too broke to updating your software is sad .