Rocker arms. How do they compare

[Dodgeboydan]

I searched around quite a bit for this, but wasn't able to find the answer. I'm building a red clone and it will be getting the Isky Black Mamba cam, as well as 26 lb springs, stainless, stock size valves, a gx160 head, and flat top standard bore piston. I'm torn on rockers to use. I am under a fairly tight budget, so I was looking at either standard pivot heavy duty 1.3 stamped rockers, or the Champion shaft rockers. I feel as if I'd be leaving some power on the table with the champions, but I'm thinking they should be more durable. Which would you guys recommend and why?

 

[vwfan79]

I am planning on going with the Champion rockers due to the durability, I have seen a 1.3 rocker break at about 8100 RPMs. I will be spinning close to 8500 so I want the strength and I don't think the small amount of power is going to be noticed.

 

[Stangrcr1]

It is way better to build for longevity than all out power.

Sure, you may get 1 or 2 more hp overall, but WHEN it breaks, you are up chit creek.

 

[Txpowdercoater]

go beefy

 

[deesel]

It depends on how good your port work is on your head as to how much power you gain with ratio rockers. My guess is with a stock or even a mildly ported head- the black mamba cam wont benefit much at all with higher ratio rockers. Probly an extensively ported head would benefit more with ratio rockers but i doubt it would be even 1hp.

 

[redgokart]

i recommend an aluminum flywheel because they are safer that the stock flywheel and they increase performance.

 

[Dodgeboydan]

Ok. Sounds like I should go with the champions. I forgot to mention that it's getting an ARC flywheel and billet rod, and the head is going to be pretty heavily ported, but not to huge since I'm staying with stock size valves

 

[minidragbike]

Some heavy duty 1.3 rockers will hold up forever, even with heavy dual springs. It just depends on which ones you have.

 

[Dodgeboydan]

Some heavy duty 1.3 rockers will hold up forever, even with heavy dual springs. It just depends on which ones you have.

Which heavy duty 1.3's have you used?

 

[minidragbike]

Which heavy duty 1.3's have you used?

I have used many, your best bet is to take a picture of them and post it up.

 

[saychz316]

Which heavy duty 1.3's have you used?

i have raceseng shaft mount rockers that are absolutely beautiful, and strong to boot. however they are spendy.

if you are looking at a stock style rocker that is heavy duty, the nr-racing.com 1.3 billet steel rockers are a no brainer. they do cost a bit though at 89 bucks a set. they make them in 1.2 or 1.3 ratio if i remember right. pretty damn tough. have spun mine to 8k, no issues when i was running them. ran them with 40lb dual springs as well. they are now in my wifes bike, and still going strong. her motor is a low rpm motor though, but her valve train is stout, and i have no worries about it.

i have also ran some of the stamped 1.3 burris racing rockers with 26lb springs for a short spell. no issues with them either. although im not sure i would run them with any stiffer of a valve spring than that. jmo

this is all using honda rocker studs, not clone studs.

 

[Dodgeboydan]

Hmm I will look at the NR Racing ones. That is just a touch on the expensive side, but im sure it's worth it to not have the valvetrain scatter. I will have to get the Honda rocker studs also. I didn't know they were a weak link

 

[saychz316]

im not sure how much of a weak link clone rocker studs are, but i used honda studs for peace of mind. maybe somebody can chime in about the strength of clone studs and how well they hold up to say a 26lb spring. i know they will hold an 18 lb spring no problem. but 18lb springs coil bind fairly quick.

i just didnt want any problems, thats all. like i said, now i run raceseng shaft mount rockers, so i have zero issues.

the champion rockers you mentioned in your first post are also a good rocker as well. many have used them with great success, and are a very good choice as well.

with so many options out there, its almost impossible to tell you what you need. its all really up to you.

my friend runs the isky black mamba with stock stainless valves, champion rockers and 26lb springs like you mentioned. he also lightly ported his head, (mostly cleaned it up, opened it up a bit, smoothed the ports out, i.e. removed sharp edges, etc) we also milled his head down .065 to get a smaller combustion chamber, then used a stock .045 thick gx 160 head gasket with it, and a .020 longer con rod. engine runs very well, not a real screamer, but runs really good, and pull starts fairly easy with a mikuni 22mm carb on it. his static compression ratio is 10.3-1 and runs on 91 pump gas all day long.

 

[saychz316]

for a low budget build with some decent parts, this is a good kit from burris racing.

https://id3528.securedata.net/test.burrisracing.com/merchantmanager/product_info.php?cPath=107_127&products_id=402

 

[ole4]

keep in mind that when using the shaft mounted rockers like raceseng, burris or champion that they cannot move out of alignment left to right so no guideplate is required.

 

[Dodgeboydan]

Thanks for all the info everyone. I suppose what I'm after is trying to build as good of a runner as my budget will allow( isn't everyone:laugh. That why I was trying to figure out whether to go towards more lift at the valve, or cut my losses and go for durability. Obviously, I want both, but I know with a budget comes compromise. It's going to be on alcohol with a Tilly. Ideally, compression will be around 12.5-13:1, which I know is going to take some work to get, if it's even possible with off the shelf parts. I also thought about making a rocker stud girdle on my mill to help valvetrain stability

 

[ole4]

IMHO I would use the champion rockers from Isky. They are inexpensive and durable and you get away from the guideplates. Only negative is the extra lift under the curve of ratio rockers.