One more cam ????

Reply Subscribe

Thread Tools

Search this Thread

Jan 23, 2012 | 10:44 PM

#11

av8or

Road Master

Joined: Jul 2009

Posts: 1,052

Likes: 12

[quote=Shredding rubber;9299030]I gotta ask. Does that spring raise oil pressure by restricting flow. I was under the understanding that a Twinkie's lubrication system was based on the idea of high volume low pressure. Please explain why. I am changing my cams in a couple of weeks and will do this mod if you can tell me why.
Thanks
I have wondered about this as well. I have an indy friend saying it's a must, and others saying it's a waist of time on the twin cams.

Jan 24, 2012 | 05:52 AM

#12

roadkingharry

Road Captain

Joined: Mar 2008

Posts: 712

Likes: 55

From: Punta Gorda, Florida

Quote:

Originally Posted by Shredding rubber

I gotta ask. Does that spring raise oil pressure by restricting flow. I was under the understanding that a Twinkie's lubrication system was based on the idea of high volume low pressure. Please explain why. I am changing my cams in a couple of weeks and will do this mod if you can tell me why.

There's info here about the spring : http://www.baisley.com/oil_spring_product.htm
When I changed my cams I got a price from a local indy, JD's cycleworks, who has worked on a lot of bikes here at the forum. He told me about using this spring so when I decided to do the cam and big bore project myself, I figured if it was good enough for him, it was good enough for me. There's no downside to it, easy install and it costs like $12. You decide.

Jan 24, 2012 | 07:15 AM

#13

tbonetony06

Outstanding HDF Member

Joined: Oct 2011

Posts: 3,492

Likes: 19

From: Illinois

While you are in there have you given any thought to just upgrade the whole area with the SE hydralic cam tensioner upgrade kit, new plate and the new bigger oil pump that comes with it? I think it's money well spent and better for your bike in the long run too, IMHO that is! I do agree though if you just do the cames to do the bearings while you are there though. That much I would do.

Jan 24, 2012 | 04:09 PM

#14

oct1949

Club Member

Joined: May 2007

Posts: 145,895

Likes: 821

From: 40 miles Northeast of Indy..

Quote:

Originally Posted by Night_Train

Interesting numbers you have there, are you riding around at 5000 rpm's with an average of 45 mph ?
Rpm's are measured at the crank, since we are dealing with a 4 cycle engine, the cams rotate once per two crank revolutions. Possibly I didn't understand your numbers?

Ur right my math if Off.

I redid the numbers...

I was trying to show how much wear a bike with 6k on her would have.

If one averaged 2500 rpm's at 40 mph, then in one hr of riding the motor would turn
approx 150,000 rpms and traveled 40 miles.

If so, then take 6k / by 40mph average -- so it'd take approx 150 hrs of riding to get 6k.
Then if a bike turned 150,000rpms per HR.

Then it'd be 150,000rpms x 150hrs = 2,250,000 rpms Approx on a bike with 6k miles.
So that'd be 1/2 for the cams... so it'd be 1,125,000 turns on the cams.

NOW.
I've just read the most lifters go 100,000 miles,,, more or less.. (And most Wrench's say to replace them at cam changes with 15,000 miles or over.)

So at 40 mph average, divided into 100,000 miles it'd take 2500 hr of riding to get to the average useage of a lifter.

Then 2500 hrs, times 150,000 revs per hr, The total rpms that a bike with 100,000 miles should be around = 375,000,000 rpm's..

Now as U stated the cams only turn 1/2 that so it's be 187,500,000.

So the point I was making that a bike with 6k miles on it has....

1,125,00 turns on it (VS) a bike with 100,000K miles on it 187,500,000 turns on it..

So I reckon this is a long way to say the the lifters has less than 10% total normal usage on them..

I've also read since redoing this, the early TC had lifters that didn't last long and that HD made several changes to them.. But if what I've read is right then the stock 06 bike had the newer (B) lifters, they should be unless they've been replaced. U still IMO should be OK...

But IF big IF,, any of them are leaking down then by all means,,, I'd replace them.
OR if U'll have a better peace of mind,,,, Replace them... Cost on mine in 09 was $125 or so.. don't know what they are now.......