421 serval?

[Strm Trpr]

I ran a fast clutch with 6 hd springs and no lock up on a 421 cub on gas in my dune bike long before the servals were availaible. Absolutely no problems. My opinion is do not do a lock up unless you are doing an override

Thanks for clearing that up.

[rubberneck]

I do agree with your list above, it is very important that all the components be in good shape. Probably wont need the ball and push rod, but i would put a good eye on the actuator, and just replace the hub and press plate. For the cost of a new clutch hub and pressure plate its not worth skipping it and having to go back in later. The very most important thing people seem to forget all the time is cable maintenance. 6 HD springs isnt really that bad as long as you have a good cable (I prefer oem, the motion pros are not the correct length) and keep it lubed. When you call jeff to order your parts get a cable luber from him and lube the cable every weekend of riding. Makes a huge difference. He also has the ez pull levers. Just listen to him, he will get you everything you need

[barahonapr]

Stem and rubberneck thanks for all the info guys. I will definitely ask jeff on what route I should go I just wanted to know more about my options and really know what's going on if that makes any sense..Haha

[RagunCajun]

It's a good list but not all is needed.

 

Id personally recommend a dunable n-down 1-5 override and skip other trans mods.

 

I run a slingshot lockup. Cheap and you can fit it under the stock case. I run 3 hd/regular springs. It keeps the clutch pull easy enough for all day riding.

[rubberneck]

depends on what kind of riding you are doing override might not be the best choice.

[barahonapr]

I wont b riding dunes or trails..I ride on the roads and open areas..so im wondering if a lock up is needed for that..

[RagunCajun]

No, you dont need a lockup. fast and RJATV both make a clutch that will hold.

[barahonapr]

Alright well I guess I don't..Haha don't think jeff said I needed one anyways..ill talk yo jim about what I should go with tomorrow

[RagunCajun]

Jeff as in FAST jeff? Hell, if you are ordering from him, just ask the man. He will tell you what you need. I trust a good builder far more than forums.

Edited September 5, 2011 by RagunCajun

[barahonapr]

Haha yes jeff from fast just haven't had time to call him since we are flying from savannah Georgia to death valley in California in blackhawks..long days and by the time I get off they are closed and all I have is u guys..thanks for all the help btw

[CFH87]

What is a top case fill? I know what port matching but what is the purpose of a top case fill.

[dirtydownunder]

on the out sides of the transfers, you case fill so there is more area for the base gasket to seal on. (when you case port for a cub, the transfer walls get pretty thin.

[CFH87]

Oh would I have to report match my cases for a serval? I had mine matched for stock cyls.

[dirtydownunder]

yep.

[beebs]

I also had my case matched to my stock cylinders and now have a cub. Is there any other downfall to not re-matching to the new cylinder other than a couple of H.P?