Cracked Rocker Bearing (Second Time)
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From: Munich - Germany
Joined: Sep 2014
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Darn! I've seen some interesting videos from military manufacturers of engine setups to check real-time performance. Pretty neat stuff.
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Joined: May 2018
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From: Munich - Germany
Could it be that this one particular valve spring is out of spec and create to much pressure?
Maybe somebody in the production line messed up, used a spring wire wich is to thick by some tenths of a millimeter or mixed a spring wich looks similar but is meant for a different engine in this set.
Or is the particular valve guide to long?
Maybe somebody in the production line messed up, used a spring wire wich is to thick by some tenths of a millimeter or mixed a spring wich looks similar but is meant for a different engine in this set.
Or is the particular valve guide to long?
Joined: Aug 2016
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From: US129 Maryville, TN
Charper, I know you're attachment with URGE and all the good work you are doing with reviving these motors. I'm a thin film coating specalist, tenured in years of developing functional coatings &engineered solutions. In my formative years, I earned my PhD in development of bespoke coating systems so understand the difficulty in your builds. I find this work really interesting and you're approach is superb, which is a excellent way forward for the F20C. With that said, you're wrong about fatigue in this case. Its twice now on the same valve / cam profile, which I've narrowed down to the cam itself. The rocker arms were a good low milage set and crack tested & inspected prior to install, fatigue twice is not likely. The discussions I've had with Patrick have already highlighted that these camshafts don't work with well with other spring setups (several failures noted on other springs). That's telling me the shaft isn't made correctly, with suspicion being around the deceleration of the lobe causing bounce. Given that these camshafts don't sit central to lobes or in the caps, reinforces the concern shaft design. I know of multiple other UK S2000 running the same springs set ups as mine with significantly more aggresive cam profiles, with 14-15mm lift VTEC & 11ish mm non-VTEC without issue.
As I've said to Patrick, the intention is to get time with my QC inspector to have the camshafts CMM inspected. This is for curiousity to try determine the issue at hand and put rest to any other concerns. Realistically, despite the support from URGE, I can't help but feel I've been sold a pup. If these cams can only work with the URGE spring/retainer combo, its a bit gash tbh.
As I've said to Patrick, the intention is to get time with my QC inspector to have the camshafts CMM inspected. This is for curiousity to try determine the issue at hand and put rest to any other concerns. Realistically, despite the support from URGE, I can't help but feel I've been sold a pup. If these cams can only work with the URGE spring/retainer combo, its a bit gash tbh.
My relationship with Urge is just as an engine builder and development. His cams selling doesn't do anything for me, so I say this with not much of a dog in the fight. - I had suspected the issue was the vtec crossover transition being too aggressive. My Vtec engagement is now solely based on rpm and not throttle %. That seemed to help, but a mis-shift more often than not would cause a broken non-vtec rocker. I have since put in a known low-milage set of rockers that spec accordingly. The difference between these and every other set in my shop is pretty astounding. I have yet to break a rocker with the new set.
Last edited by Charper732; Aug 7, 2025 at 04:58 PM.
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Joined: Dec 2021
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Charper, I know you're attachment with URGE and all the good work you are doing with reviving these motors. I'm a thin film coating specalist, tenured in years of developing functional coatings &engineered solutions. In my formative years, I earned my PhD in development of bespoke coating systems so understand the difficulty in your builds. I find this work really interesting and you're approach is superb, which is a excellent way forward for the F20C. With that said, you're wrong about fatigue in this case. Its twice now on the same valve / cam profile, which I've narrowed down to the cam itself. The rocker arms were a good low milage set and crack tested & inspected prior to install, fatigue twice is not likely. The discussions I've had with Patrick have already highlighted that these camshafts don't work with well with other spring setups (several failures noted on other springs). That's telling me the shaft isn't made correctly, with suspicion being around the deceleration of the lobe causing bounce. Given that these camshafts don't sit central to lobes or in the caps, reinforces the concern shaft design. I know of multiple other UK S2000 running the same springs set ups as mine with significantly more aggresive cam profiles, with 14-15mm lift VTEC & 11ish mm non-VTEC without issue.
As I've said to Patrick, the intention is to get time with my QC inspector to have the camshafts CMM inspected. This is for curiousity to try determine the issue at hand and put rest to any other concerns. Realistically, despite the support from URGE, I can't help but feel I've been sold a pup. If these cams can only work with the URGE spring/retainer combo, its a bit gash tbh.
As I've said to Patrick, the intention is to get time with my QC inspector to have the camshafts CMM inspected. This is for curiousity to try determine the issue at hand and put rest to any other concerns. Realistically, despite the support from URGE, I can't help but feel I've been sold a pup. If these cams can only work with the URGE spring/retainer combo, its a bit gash tbh.
Both me and my buddy have urge cams with the urge valve train. I have about 6 track days on my engine, he has about 15. This past weekend his roller bearing cracked on cylinder 4 intake side. He had the rr7 cam. Just earlier I was prepping my car for a track day tomorrow and heard a metallic clicking noise. Pulled thr valve cover and sure enough my cylinder 3 rocker bearing was Crack and I have the rr8 cam. I have also bought two blown motor with urge cams that have Crack roller bearings. At this point, I don't know if I want to stay urge cams anymore. My engine is too expensive to risk. On the other hand, some of my buddies on the endyne head and 4p cams are doing well. That might be the move next or go back to oem cams.
Joined: Jul 2013
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To me this seems more like a camshaft design issue, perhaps too intense on the ramp. The OEM valvetrain is already pretty on the edge as far as opening speed for the valves, if you're going to have a more aggressive ramp up to .050 you're going to induce more force on the rockers. If anything the OEM springs probably aren't up to the task, you would need a stronger spring, which on the F2xC is already on the edge. If you install a stronger spring you start getting into diminishing returns because you're adding friction to the valvetrain.
Joined: Oct 2009
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From: Ontario Canada
I have been away from this thread for a bit, but looking at the pictures those retainers look like total junk to me, they just look weird in how they sit on top of the spring. I can't say they are causing any issue or not but I would not want to run a retainer that sits like that.
Joined: Sep 2016
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From: the Netherlands
Thread Starter
Joined: Mar 2013
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Interesting to hear that several others are having issues with the URGE cams. I had plenty of discussions with Ian @ Clockwise about the valvetrain and cams. His thought was the ramp rates being overly aggressive, which is why he doesn't spec' cams that way. As Charper highlighted, these bearings do wear and will fatigue. I think as many of you will likely agree, the ramp rates & potential for increasedf fatigue is resulting in cracked bearings. I've opted to put the OEM cam's back in and consider a 2.5L for the 2027 hill climbing season.