Camshaft upgrade

[jlewisjr22]

Hey guys so I have a 2000 Yamaha roadstar xv1600 and my friends have the roadstar warrior. Now one of them have been saying that they have seen once that someone has succeeded in swapping a warrior cam into one of my bikes. However he can’t seem to find the write up about it. Does anyone have any kind of information on this swap?

[Lug Nut]

Why on earth not just buy the appropriate cam from Patrick a racing for your bike? Just a cam swap won't do much from what I have seen...

[davej]

It won't fit a 1600 but will fit a 1700. there is really not much advantage using a warrior cam. I used to have the specs on a stock 1700 cam and a Warrior cam and it wasn't much difference. Patrick is the only available cam I know of unless you can find a shop to weld and custom grind one for you. Good Luck.

[Duke]

The 1700 cams will physically fit, but has way to big of lift for a 1600. If you have a set of 1700 cams, you can have them ground to any 1600 specs. The lobes on a 1600 are much smaller due to the 1600 heads having a 1.9 to 1 rocker ratio. In 2004 RS went to 1700 and a head redesign with a 1.4 to 1 rocker ratio which required a larger lobe on the cam for the same valve lift.
I have talked with some people that have put 1700 heads on the 1600 using the 1600 cams, but as I mentioned to them, their valve lift was decreased from .356" to .262". It will run, but with reduced power.
The Warrior heads use 1.4 to 1 rocker ratio and has a different intake and exhaust port configuration. The only way to use them would be to use that fuel injection set up, or special custom manifolds.

The line-up pins, jugs to heads, have different pin sizes, so you would have to have 4 custom stepped pins made to work properly.

[Duke]

The rocker arms are not interchangeable.
If a person wanted to make there1600 into a 1700 by just using just the jugs,pistons and head oil line, keeping everything else the same, it can be done. I guess I'm trying to say, 1600 heads can only use the 1600 cam profiles. Without grinding a 1700 cam down to 1600 profiles, the valve lift is to much for a 1.9 to 1 ratio.
Lobe lift on a 1700 is .245", X 1.9 rockers = .4655" = way to much without a lot of modifications.

[davej]

Duke so you are saying that the 400 lift that Patrick sells is as high of a lift as you can go? The other day someone said they had a 565 aftermarket cam.Even with a 400 lift I had to change the valve springs, I wonder how much room there is before valves and pistons kiss each other?

[jlewisjr22]

So duke your saying that the 1700 jugs and heads will just swap over to my 1600? Or is there more involved?

[LUV4RS]

I love all the technical data I find on this site. On a very non-technical side note, I test rode a 2005 midnight star yesterday of which the owner told me larger cams had been installed to make it feel more like a Harley. The bike ran strong and sounded good(de-baffled stock pipes), however, after 10 mins of riding both my arms felt numb from the excessive vibration. Not sure if this was from larger cams being installed or if there was something else going on with the bike.

[roadiemort]

I don't know anyone that put cams in without high compression pistons. HC pistons without HO cams yes.

[Duke]

I'm running the 10.5 JE pistons, but the cam is stock. This helps improve fuel mileage, but when it's hot you need good fuel. Stock cams are fine if your keeping the RPMs down. If I did anything to get more air, I would go with larger valves.

[davej]

Duke, I have +2mm valves with hand ported heads from Pro 1 Racing in Az and it was a great improvement. My PR cam likes RPM and not lugging at all. Even with all the mods to my engine if I ride normally at hwy speeds around 70-75 I can get into the low 40's mpg. But twist it a couple times and I can get into the 20's mpg.lol

[Duke]

Jlewis22, You can put the 1700 jugs, pistons, heads and cam on a 1600 engine, but you will need the 1700 intake manifold, cam, push rods, head oil line and frame mount on top of the heads. Like Roadiemort was talking about, check the cam clearance in the case.

Dave, when I was checking clearances, I'm thinking that the stock spring retainer to the valve guide would need more clearance. At .4655" I beleave the valves were fairly close to the pistons, but I didn't clay the clearance. At .565" I'm sure a person would need to valve cut the pistons, not to mention the valves, springs, push rods, etc..

I have the Speedstar CNC ported heads that I hand ported out a little more, so I might put the 1700 jugs and pistons in my 1600 using the 1600 heads. I have the stepped line up pin made and the jug fins matched for the heads.

[davej]

I have the adjustable push rods and push rod tubes,IMO that is the only way to do it, The collapsable tubes saves a lot of work. I kind of figured the PR only offers a 400 lift cam for some reason. Him cam profile does run good and still idles good. Call me old fashion but I'm not a big fan of CNC ported heads compared to a good hand port job. I found Charlie at Pro 1 Racing and spent a lot of time watching is Youtube videos and talking with him on the phone before I knew he was a old school top notch porter. When I talked to PR about flow numbers they told me they have no idea what they flow. That the computer design say that they flow properly and that they don't even check flow on a bench. Well in my old time mind no 2 cast are the same so when a cutting bit goes in it may miss a spot because of the cast imperfection and create a dead spot. This was confirmed by Charlie at Pro 1. He said when it happens cnc porters just go in and put a finish on that spot to make it look uniform. He goes back in and reshapes it to get rid of any dead spot. He also does a custom valve seat profile to maximize flow. I also sent him my intake manifold and he touched up the porting and port matched it and flowed it with the heads Here are some pics of his work. Seat profiles and porting.

[Duke]

That is really cool to me. Like you said, adjustable push rods are the way to go.
I too, have learned a lot about porting through out my life. I'm just like you about old school and CNC porting, and that's why I finished up the heads I have. I only wish that I didn't get rid of my valve grinding, seat machine and air velocity meter. I use to rebuild and custom port heads for racers and friends. There is a lot to know when porting heads to make them flow better at lower and higher air velocities. A lot of people think that bigger is better and that isn't necessarily true. Air is a fluid, like water, it flows, and that's the way I think of it when porting.

[davej]

Duke, Charlie from Pro 1 has a bunch of youtube videos and explains a lot about porting and seat areas. You got it right bigger isn't always better, only if it is in the right spot. I hand ported mine just a bit (more of just a good clean up) when I did the big bore and it ran good. When I got the heads back from Charlie it now runs GREAT!!! Duke look up his videos I think you would like them. Youtube either Pro 1 Racing heads or Short block Charlie. He has quite a few videos that shows work on HD heads. Believe it or not he was 1 of the only porting shops that would port a non HD. That is besides Patrick Racing. The rest just want to CNC port HD heads. I must have called over a dozen places across the country.

[Duke]

That's good to know Dave, Thanks, I will have to check out his videos.