Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[skippy49]

I've got an 03 SERK with only an SE air cleaner and Rinehart true duals and I'd like to replace the stock cams with a gear drive to eliminate the tensioner problem, and possibly increase the compression ratio a little at the same time.  I don't want to do much head work right now other than something to increase the comp. ratio a little, either through milling or thinner gaskets.  Basically I just want to do a mild improvement over stock with a minimum investment.  Most of my riding is done at 40-70 mph, usually solo, but two up on trips.  
  Also what would be a good gear drive to just replace the cam and do nothing to the heads or compression.  I'd really like to increase the comp at this time, but not if it's going to cost me another $500 to $1000 above the cost of doing gear drive cams.  BTW, I'll be doing the work myself so labor shouldn't enter into it.

Any suggestions are appreciated----including the suggestions to do nothing!

Thanks
Steve

[Unbalanced]

To go gear drive,

26g for single rider and 37g if your going to ride 2 up.   Andrews cams.

You will prolly see the freedom clan speak up here and also choices are if you want more you could try the 55g by andrews the heads on the bike will handle the lift.  Generally most massage the heads some with this cam.   SBC / R&R / John Sachs / Speeds (uses R&R)

if you can wait a bit we may have an answer for you on the Zippers bolt in cams as well as the 557 gear drive cam that DCFireman is doing (Dawg).   I am told that Zippers has shipped me the 2 cams they have as bolt in for testing.  

-harry

[skippy49]

Thanks,   I'm not in a big hurry, just thought I might do it sometime this winter, but we won't ride much until March or April so I've got a little time anyway.
  Do you need to check the pinion runout before deciding on gear drive cams?  If so, what is the maximum it could be and still get by?

[Unbalanced]

Skippy,

Shouldnt have to worry about it the gear drive,  The gear drive bolted straight in on my 103 which is just like yours.   In some cases you may need to do some clearancing.  I believe both Jim's and Zippers both sell a tool that allows you to clearance the case yourself.   Most shops carry these anyhow.   In the case of the 103 you can put in a Andrews 55g with no issue and same with S&S 625.  They both fit straight out of the box the only thing you may have to do depending on how you order it is have the gears pressed onto the cam and place the bearings in place

-harry

[skippy49]

Harry:
   Which cam did you use on yours and did you do anything to increase the compression?  Such as milling heads or thinner head gasket?  How did you like the results of the cam change?
Thanks,
Steve

[factoryphil]

Harry:
   Which cam did you use on yours and did you do anything to increase the compression?  Such as milling heads or thinner head gasket?  How did you like the results of the cam change?
Thanks,
Steve

Steve

I'd like to know what Harry did to his also???

[VANAMAL]

im thinking of using the freedom 103 cams newly designed by them and made by andrews. i also have all the jims tools needed to change over to gear drive. pm me if intreted

[Unbalanced]

I can only share bits and pieces, because the package is not yet complete.   I can tell you what worked and what didnt work, but as of right now I still have a few issues I am playing with.  Such as waiting on heads from Zippers.

I can tell you that 55g with over 10.0 to 1 compression will detonate and ping and you can not retard the timing far enough to make it go away.   I can tell you that the Horsepower Inc 53 mm throttle body pushes to much air / fuel when you dont have head work.
I can tell you the stock heads arent high velocity.  I can tell you a cometic gasket / 55g can produce 118 / 112, but that when you have 10.25 compression it will detonate.   195 lbs of pressure per cylinder on a compression test is too much for a 55g.  

Advise not using the 10.5 to 1 pistons with a hemi shaped head even if you deck them to end up at 10.25 to 1.

As it stands today I do not have a combination that I would endorse totally.   That may change when  I get some headwork.   However the 55g was the stump pulling kind of torque I could grow to love for sure.   I am sorry I don't have a complete package to share yet, which was why I have only posted on things that I can say do or don't work, and that is based on the experience of doing them.

If you need more info's or have pointed comments shoot me a pm or email me at unbalanced@bellsouth.net

-harry

[syclone]

I can only share bits and pieces, because the package is not yet complete.   I can tell you what worked and what didnt work, but as of right now I still have a few issues I am playing with.  Such as waiting on heads from Zippers.

I can tell you that 55g with over 10.0 to 1 compression will detonate and ping and you can not retard the timing far enough to make it go away.   I can tell you that the Horsepower Inc 53 mm throttle body pushes to much air / fuel when you dont have head work.
I can tell you the stock heads arent high velocity.  I can tell you a cometic gasket / 55g can produce 118 / 112, but that when you have 10.25 compression it will detonate.   195 lbs of pressure per cylinder on a compression test is too much for a 55g.  

Advise not using the 10.5 to 1 pistons with a hemi shaped head even if you deck them to end up at 10.25 to 1.

As it stands today I do not have a combination that I would endorse totally.   That may change when  I get some headwork.   However the 55g was the stump pulling kind of torque I could grow to love for sure.   I am sorry I don't have a complete package to share yet, which was why I have only posted on things that I can say do or don't work, and that is based on the experience of doing them.

If you need more info's or have pointed comments shoot me a pm or email me at unbalanced@bellsouth.net

-harry

I respectly disagree on a couple of points. A 53 mm throttle body will flow no more air than the motor can handle, and fuel delivery with any size injector is determined by the mapping. Large throttle bodies on carbed bikes can hurt performance cause the signal to the carb (velocity) can really screw up fuel delivery. On EFI bikes, properly mapped, that has been proven not to be the case.
I run 55gs at 10.5:1 in my Night train. Carbed bike with DTT igniton (correct timing slope) and I cant make it ping.

[Unbalanced]

I respectly disagree on a couple of points. A 53 mm throttle body will flow no more air than the motor can handle, and fuel delivery with any size injector is determined by the mapping. Large throttle bodies on carbed bikes can hurt performance cause the signal to the carb (velocity) can really screw up fuel delivery. On EFI bikes, properly mapped, that has been proven not to be the case.  
I run 55gs at 10.5:1 in my Night train. Carbed bike with DTT igniton (correct timing slope) and I cant make it ping.

The problem isnt the motor cant use it, the problem is that its not moving fast enough to take advantage of.   The bike actually ran better with a smaller intake and throttle body in this case due to the heads not being able to use the air in a form that would make it advantages.
eg. The heads stock arent high velocity just volume.  Very top end sure it can take the air, but down low it became a stuck pig.

If you happen to call Ralph at Andrews he is the lead cam guy for Andrews he will tell you that on a 103 stroker not to run the 55g over 10.0 to 1.   He also informed me before telling him what was going on that i had excessive pinging / detonation.   Now for me that was good enough reason to go with his recommendation to a more latent closing intake than the 55g.   Funny part is all the detonation went away.  You can refute that all you like, but in this case the fact of the matter is it resolved the issue.

Another point could be your actual compression or adjusted compression maybe lower than you think it is or mine could be higher than stated.   I have the bike in the shop right now just to reverify this.   What they are checking is volume in the heads with the cometic .030 and the decking of the 10.5 to 1 pistons.   I should know better on this on Tuesday next week that is the goal anyhow.

[syclone]

UNBALANCED....What was the engine build ..pistons? head gasket? that you were running with the 55g cams. I'm curious cause the CVO motors all are at about 165 ccp which is really only about 8.7:1 comp ratio.  An  .030 cometic alone will get you only a litttle over a .25 bump in compression. Using a domed piston in a non-matching hemi chamber with no quench area at all can really play havoc with swirl and mixture distribution .....So it has detonation..put in a cam with a later closing intake...cut the cylinder pressure to stop the ping....which is why the only guys I know of at this time welding up CVO heads and remachining the chambers for use with non-flat tops..is SBC. $999.00.
(I've seen some CVO heads with chambers over 90 cc)

[nidan]

37G work best at 9.8:1 , if you get too much higher you can run into pinging and detonation . I was looking at Hi Comp pistons and Andrews cautioned against them for this and the 26G.  

[skippy49]

Getting back to the original question, if all I wanted to do was replace the cams with gear drive, what would be a good cam for that?
Then if I did want to work on the heads and get the comp. up a little-don't know what's best-welding or milling- then what would be a good cam to use with the head work?  Is there a cam that would work now if all I did was the cams, and then next year worked on the heads and still use the same cam?
  A lot of questions, I'm just trying to figure out what I can afford to do and what is the best route to take for me right now.
Thanks for any extra suggestions

[Twolanerider]

Skip, you're asking that question at a fortuitous time.  There is honest to god research going on almost literally as we speak.  

Freedom Cycles out west has just released a gear drive cam for the 103 motors that is designed to be used for replacement in a motor with otherwise stock internals.  A couple of the members here have already done the installs and have dyno sheets posted followed by conversations of the pros and cons.  Do a search by "Freedom, gear drive" and see what you find.

Zippers back on the east coast has just released to cam sets that are still, basically, development pieces and sent them to our own Unbalanced member of the site.  Harry (Unbalanced) has written that in the next few weeks he'll be working with both of them and reporting results.  These are also cams designed for our 103 motors.  

Zippers also has a cam from their RedShift line that has been a standard item for them that also looks like a promising bolt in replacement for an otherwise stock 103.  DCFireman has his bike at their shop now (or in a very short period of time) for them to do an install and tune and then be able to report back on that cam set.

So, if patience do'th allow, hang tight a bit and get these other reports back.  The Freedom Cycles reports have already started rolling in.  Soon we'll be able to compare all the products together.

[DCFIREMANN]

OK guys it's O' DARK THIRTY here in the mountains. I was going to make the trip to Zippers tomorrow morning, BUT we are under a HEAVY SNOW WARNING for tonight and into tomorrow mid day. So I said to myself and I quote "SELF" what would you do in a case like this. Self looked back at me and told me to get my ass going and since I had some part time work about 1/2 hour from Zippers THE EAGLE is going on the trailer this AM for a trip over there and I can kill two birds with one stone.

I will post something on the Zippers thread also and tonight when I get back home and I might have a time line. I do know they had a dyno down not sure which one but I would assume the Land/Sea model.

Be Safe

THE DAWG