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Discussion Starter #1
So we tore into the cylinder head to find out what my noise and loss of power issues were, and sure enough as we expected the intake valve springs were broken...all of them. My mechanic said he's not surprised. He had a gsxr in recently with broken kibble white springs also. So needless to say I'm not going back with the kibble white springs this time around.

What I need is some good suggestions or recommendations on what valve springs are worth a shit. Only other ones I've heard of guys running are carpenter, but I don't want to get into a spring that is too stiff that will rob power either.

On another note, while the head is off we are going to mill it down a bit, do a valve job, and possibly a port n polish job on exhaust side. Anyone have any experience/results when porting the exhaust ports?
 

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were those springs shimmed? fixed a bent valve/broken guide for a fellow member with kibblewhites, those springs shimmed over .100. about the only thing that will break a spring is coil bind, and all 8? 30 yrs building engines, installing up to 520 lift cams,never seen anything like that. sounds like some extreme seat pressure to wear out cam and break springs. u also need to ck int. seats valve seal from hammering by valve. stk. springs ok with 08 race int. dont like carpenter springs, lose too much tension quickly. ape may be good alternative. as far as losing power from spring pressure, springs store energy used to compress, returns same amount on valve closing side. lobe/ bucket friction increased though. decking will provide more power, good cnc vj will do same increasing flow and ex. porting will definatley make a difference. often overlooked and a mistake to do so, everyone says ten head factory ported, not on ex. it's not. sorry for the problems u had, but now is a good time to make several more hp with decking, vj, and ex. porting. have a good builder for vj and deck. lmk if u need any help with ex. porting, done a few. pic's under profile. good luck on repairs/upgrades.
 

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Unless there is a pressing need to do otherwise, OEM is usually the most reliable configuration.

Only thing the gen 1 really needs is better retainers, but even then ... the OEM 2008-model retainers are drop-in replacements and are a little thicker in the critical area.

So my vote is to use the OEM springs, the 2008 retainers, and then keep the valve lift within the bounds of what those springs will handle. (I don't know how much lift they'll handle ... in my recent gen 1 rebuild, I picked Web camshafts that are about the same lift as stock ... reason: we know it won't go out of bounds with the stock valve springs.)
 

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what go faster said, springs are overrated for most mild cams being used. i run the same webs as go faster described with stk. springs shimmed .025. for 3rd year. enjoy those cams, they work great, last pass at dragbike natls. 3 wks ago was 159.48 on stk. springs.
 

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I've only ridden mine a bit on the street with those cams to get some break-in and shakedown done, and it still has the stock exhaust on it complete with catalyst (!) and it seems pretty healthy!
 

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Discussion Starter #6
Hey guys thanks for the good info. I have titanium retainers already so good there. We are also replacing the valve seals. Im running 08 race cam on intake and stock exhaust cam. The only reason I was really using aftermarket springs in the first place is the combination of bigger cam and I have 500 rpm extended red line. Is that an issue for stock springs?
We are def milling head, and doing valve job. Ive seen enough gen1 heads to know only the intake side is ported from factory. Exhaust side is rough, but my machine shop guy said with such a mild cam I would get no benefit from porting and polishing the exhaust ports. What do you think?
 

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Discussion Starter #7 (Edited)
were those springs shimmed? fixed a bent valve/broken guide for a fellow member with kibblewhites, those springs shimmed over .100. about the only thing that will break a spring is coil bind, and all 8? 30 yrs building engines, installing up to 520 lift cams,never seen anything like that. sounds like some extreme seat pressure to wear out cam and break springs. u also need to ck int. seats valve seal from hammering by valve. stk. springs ok with 08 race int. dont like carpenter springs, lose too much tension quickly. ape may be good alternative. as far as losing power from spring pressure, springs store energy used to compress, returns same amount on valve closing side. lobe/ bucket friction increased though. decking will provide more power, good cnc vj will do same increasing flow and ex. porting will definatley make a difference. often overlooked and a mistake to do so, everyone says ten head factory ported, not on ex. it's not. sorry for the problems u had, but now is a good time to make several more hp with decking, vj, and ex. porting. have a good builder for vj and deck. lmk if u need any help with ex. porting, done a few. pic's under profile. good luck on repairs/upgrades.
Also, no the springs were not shimmed. All my mods are listed in sig. Head was stock first time around just titanium retainers, KB springs and cam, degreed 110/102, changing that this time too. If I use stock springs with 08 race intake cam should I shim the stock springs any?
 

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I was revving my 08 with KENT cams 10.2mm lift intake/ 8.8 exhaust and reved the shit out of it up to 14k rpm,never had an issue,but I removed the head recently and found all intake piston pockets decarbonized :badteeth:,which means the pistons had some contact with the valves, you will probably be fine with your cams until 13.500 with stock 08 springs IF PtV is OK during installtion,I had mine at ~ 1mm for intake a bit more for exhaust.
I have installed APE springs on the 08 retainer,although it's not optimal because these springs are designed for 1st gen retainers and don't sit 100 % straight on the 08 stock retainers.
 

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Discussion Starter #9
Ok so another question. Do all first three gens share the same stock springs, and anyone know if they are discontinued?
 

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Sorry to hear :sad: I just installed Kibbles as well.
In your other thread ("ticking above 8k"), you mentioned the int cam was ruined as well. I'm wondering if, as the cam went away and the ramps became more abrupt, that would tend to "shock" or "ring" the spring. Possibly, the cam failed first (from too much "over the nose" pressure), and the springs then failed? Either way, a strong argument for the OEM springs.
Multiple failures are very uncommon in my experience as well, FOUR broken springs WOW!! :headshake
 

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Discussion Starter #11
Sorry to hear :sad: I just installed Kibbles as well.
In your other thread ("ticking above 8k"), you mentioned the int cam was ruined as well. I'm wondering if, as the cam went away and the ramps became more abrupt, that would tend to "shock" or "ring" the spring. Possibly, the cam failed first (from too much "over the nose" pressure), and the springs then failed? Either way, a strong argument for the OEM springs.
Multiple failures are very uncommon in my experience as well, FOUR broken springs WOW!! :headshake
8 broken springs... Not sure man. My mech just hates KW, says they're junk. He has a lot of experience in AMA for kawi and Suzuki. CyckeWerks Ft Worth TX.
I just tt him a sec ago and he said now if I go with oem springs I cant use my titanium retainers because I will lose a ton of seat pressure. I suggested the 08 retainers because theyre thicker, He said well if theyre thicker in the right place it could increase seat pressure.. SO shit Im stumped. ANY SUGGESTIONS. Should I just run stock springs and retainers??
 

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FWIW, i had my engine built last summer from a very reputable builder who said OEM retainers were fine and actually better than Ti from his experiences and he builts boosted Busas that dyno well over 300hp. Not sayin, just sayin. We used Carpenter springs.
 

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There seems to be a fair number of people using OEM springs with '08 retainers. Appears to work well (if shimmed), even with an extended rev limit and "kit" cams. Wasn't there a problem with KW's supplier around the time you did yours?
I think I remeber a thread about that, and Cycle Concepts being bugged about it as well.
 

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Discussion Starter #14
There seems to be a fair number of people using OEM springs with '08 retainers. Appears to work well (if shimmed), even with an extended rev limit and "kit" cams. Wasn't there a problem with KW's supplier around the time you did yours?
I think I remeber a thread about that, and Cycle Concepts being bugged about it as well.
Man Idk. I got mine from cycle concepts too. I would need to know how much to shim them if I used the 08 retainers. I'm thinking about just using 04 oem springs and retainers and hope they hold up to the beating.
 

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Discussion Starter #15
FWIW, i had my engine built last summer from a very reputable builder who said OEM retainers were fine and actually better than Ti from his experiences and he builts boosted Busas that dyno well over 300hp. Not sayin, just sayin. We used Carpenter springs.
Ya my builder said oem retainers would be better too because of weight of titanium ones. I've just read that 1st gen retainers have been known to break, especially with race cam and extra rpm. ???
 

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Ya my builder said oem retainers would be better too because of weight of titanium ones. I've just read that 1st gen retainers have been known to break, especially with race cam and extra rpm. ???
Several threads on the forum about retainer breakage, Garth has seen a few. Plus there's been ads on ebay (in the last few weeks), for a complete motor with broken retainers, as well as a cyl head with 3 broken retainers (both Gen 1). Not sure I've seen anyone have a prob with Gen 3 or current production OEM retainers.

I wish I had taken the time to wiegh the Ti's vs OEM when I swapped. The Ti's were substantially heavier, thereby requiring more spring pressure to control. With the ZDDP/phosphorus being diminished in most current production oil, extra/excess spring pressure definitely can advance cam wear.
 

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Discussion Starter #17
Well that's exactly what my mech said. The oils today prob wore out cam and buckets which in turn stressed out the Shitty valve springs. He suggested Joe gibbs racing oil. Still has all the good stuff in it. So could I shim the oem springs to work with my titanium retainers and get proper seat pressure?
 

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maybe, need to measure installed spring height between base and retainer, then ck seat pressure and adjust by shim as long as you have at least .030 from coil bind at full lift. i shimmed my gen 1 springs .025 after talking with ace performance, they said i would gain another 450 rpm before valve float. i also knew i was safe to do so because i run stk. lift cams and the race cam was ..024 higher lift and many were running it with stk. springs. i would do some measuring before i shimmed stk. gen 1 springs with a .382 lift cam, cant just randomly shim springs with added lift. progressive wound springs generate high pressure when compressed to tight as in more lift, shimmed at full lift, that's why many race high lift springs are not progressive wound. they provide the necessary seat pressure valve closed and necessary but not excessive pressure at full lift. take a look at stk. 10 progressive wound spring, coils are tighter allowing less travel. they work well for what they were designed to do, but they have thier limitations.
 

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I would add that, IMHO, anything gained by shimming stock springs would be completely negated using Ti's with OEM springs because of the Ti's added weight. I'd lean toward OEM/OEM, shimmed, (but check for coil bind as Gas mentions).

A concern I would have, (sorry to bring it up though), would be; how much metal has gone through the motor? Not only as powdered iron, but any chips from when the springs broke. It sucks and you've probably thought about it, but I had to bring it up.:sad: Motors are pretty stupid sometimes, they don't always realize the things we put them through. Did your builder already bring this up? Might be worthwhile to cut open the filter and see what it caught. Maybe check the inside of the oil pump for scoring as well. You may be able to just clean it all out and be good to go, but worth looking into.
 

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Discussion Starter #20
I would add that, IMHO, anything gained by shimming stock springs would be completely negated using Ti's with OEM springs because of the Ti's added weight. I'd lean toward OEM/OEM, shimmed, (but check for coil bind as Gas mentions).

A concern I would have, (sorry to bring it up though), would be; how much metal has gone through the motor? Not only as powdered iron, but any chips from when the springs broke. It sucks and you've probably thought about it, but I had to bring it up.:sad: Motors are pretty stupid sometimes, they don't always realize the things we put them through. Did your builder already bring this up? Might be worthwhile to cut open the filter and see what it caught. Maybe check the inside of the oil pump for scoring as well. You may be able to just clean it all out and be good to go, but worth looking into.
Good call! Shitty, but good call. I have already drained the oil to check for metal shavings or debris and oil looked really clean still, j had just changed it prior to eng failure so it was super clear. Didn't see anything. Cross my fingers.
I may go ahead and just order carpenter or ape springs. Would yall recommend one over the other? And will my kibble white titanium retainers work with either of those springs or will I need to buy new retainers too?
Thanks for the help guys. Will send much rep.
 
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