cam selection

I have a 91 xr 600r and the cam and rocker arms all whent to hell a couple of weekends ago so I am going to have xr's only fix the head and top cover, but I wanted to know what kind of cam sould i run and where can I get it. Xr's only told me that the hot cam that they sell is really a crappy cam and they do not recomend anyone to use the hotcams cams in the xr 600's. They say that they do not last very long and that they can cause a lot of damage to your motor, so my question is what cam should I run and where can I find it.

P.S. what are some other good mods to do while the bike is all torn apart

well put an 11:1 compression piston in there from wiseco, put a new conrod kit in there, of course new cam and i dont know who told you the hot cam is crap cause ive gotten nothing but good reviews on it so they must be smoking crack

I can't comment on the cam, as I want maximum longevity and reliability. Same for the hi compression piston, I want to be able to use regular gas if I have to.

The following aren't mods, they are things likely to be worn.

A new cam chain tensioner, as they wear out. When I replaced mine I did a new cam chain too. Ask them about it.

Check the ring end gap. They are likely out of spec depending on how much you ride it. My bike started blowing oil out the breather and I found the ring end gap was way way past spec. The piston and bore were (marginally) OK, so I honed and put in new rings.

When I had the cylinder off to do the rings, I looked in at the transmission. Second and third gears were pretty badly pitted. This was the most costly part to fix. Those gears are expen$ive. If they break, it's new engine time.

I have seen posts in the past, that would recommend the Honda HRC performance cam ... supposedly, the HotCams hardened lobes aren't compatible with stock cam followers, quickly wearing them down ... I have no first-hand knowledge of this, but I have heard it said numerous times ... something to consider ... :crazy:

... supposedly, the HotCams hardened lobes aren't compatible with stock cam followers, quickly wearing them down ... I have no first-hand knowledge of this, but I have heard it said numerous times ... something to consider ... :crazy:

Then you've heard wrong or are getting things confused. HotCams are one piece newly machined tool steel billet designs (not re-grinds) that are about the same hardness as the stock cam and are specifically designed to work with the stock valve train components if they're in good shape. It's the other cams such as MegaCycle, WebCam, etc, that are regrinds which are hard welded and those are the cams that requires matching hard surface on the rockers / followers and using one of those cams without upgrading your valve train components will quickly wear things down.

dan3084,

XR's Only is full of CRAP to tell you that, but then again, unless you're dealing with the owner 'Freddy', then the info you're getting may be coming from somebody with less experience than your your children. XR's Only hasn't been the same since the owner died (plane crash) and ALL the staff left years ago. It's definitely NOT the same place it used to be!

XR's only didn't recommend the Hot Cam for my 650L because with this cam you can no longer use the auto decompresser. With no kick starter for backup, it's a good idea to keep the battery load low. Although I have read posts where many people are happy with the cam. I would hate to have to push start it out in the bush. The 600R has a manual decompresser and a kick starter. It should be no problem.

I prefer the stock cam in the interest of longevity. I have used Megacycle and HRC copy cams in XR600s and premature rocker wear is a factor. Whether or not you decide to go with a performance cam, a new set of valve springs is a good thing because the old stockers are probably sacked out from heat and stress, new springs will be easier on the valve train. I like R&D springs.

hey those R&D spring do they make those for xr600's cause right now the entire top end on my bike is in pieces down to the valve seals and i want to build it out before putting it back togethor

hey those R&D spring do they make those for xr600's cause right now the entire top end on my bike is in pieces down to the valve seals and i want to build it out before putting it back togethor

You can get R&Ds or Kibblewhite springs (Kibblewhites are OK too, MHO) at www.xrsonly.com also Kibblewhites at www.barnumspro.com.

Thanks for the input. I dropped the head and top cover off at xr's only and they are going to order me a honda cam and honda cam followers so that there will be no problems but thanks.

I'ver heard the rumors about the Hotcams camshaft as well. And guess what, I have first hand experience with it wiping a cam lobe and rocker. Barnum will tell you if you're running heavier springs to go with a hard welded cam and rockers for insurance. I just got mine today and it should be in tonight and hopefully a test ride tomorrow.

I prefer the stock cam in the interest of longevity. I have used Megacycle and HRC copy cams in XR600s and premature rocker wear is a factor. Whether or not you decide to go with a performance cam, a new set of valve springs is a good thing because the old stockers are probably sacked out from heat and stress, new springs will be easier on the valve train. I like R&D springs.

Megacycle cams are hardwelded which means the cam's surface is made of a stronger alloy. Did you also get your rocker surfaces hardwelded? If not stock rockers will wear prematurley on hardwelded cams.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now