one for the engine gods

[FBJ]

Hi all, I will give you a quick update on the symptoms then a bit more detail on the wifes 1170 Kat,. we bought it from a chap a few years back, he seemed to know what he was talking about and told the motor was quite trick and gave us a power curve showing 130hp, when ridden it felt like 130hp. Anyway when started from cold she smokes, normal valve stem seals., no bother there then, We went Eurokat 4 on it year before last and it used about 4 or so litres of oil, to cover 2200 miles. when cruising at 80 there is little or no smoke. the problem occurs when she pulls up into a toll or services and idles she smokes like hell after a half hour ride. I'm thinking guides, what do you think?
Anyway before I pulled the head of I carried out a compression check, I have no concerns there, all around 165 PSI and close to each other. It has a wiseco 1170 kit, high lift cams and gsxr carbs. THe cams have G4 stamped in the end. This is where i'm worried, had a look at the valve stems they all seem to be with in tolerance. howver the guides seem to be fecked good and proper, inlet limit is 0.090mm, I can move these to something like 0.400mm and more. It has covered 58000 miles. Will it be because of the G4 cams?
I have another head I got from a top chap on here (cheers Scott) however I don't want to fit that with out checking it and also knowing the G4 cams might fec it up.
I'm taking the heads to a machine shop tomorrow, he mentioned that if all the guides are fucked it could be as much as £500, ouch, what's your thoughts on that?
Thanks FBJ

[johnr]

lairy cams will always cause more wear and tear than stock stuff. thats part of the payoff for more power. but the wear on your guides whilst it may well be because of the cams cant be entirely blamed on them unless you know all the history. if the bike was built for big power and then thrashed hard, or ridden hard from cold then it may account for the wear you have. 500 quid sounds a lot for a set of guides. have you priced them up from suzuki, cos they arent hard to fit, alternatively, do you have access to or know anyone with a lathe? cos theyre not much to make if you can use one with any degree of precision.
best to get it done before the wear starts to affect the selaing of the valves themselves on their seats.

[Katgeezer]

I'm no god John but standard guides are about a tenner each so 160 quid. G4 grind is .355 lift so no need for anything special like shortened guides (which ironically are cheaper?!?!). 500quid sounds an awful lot but maybe that's just worse case scenario like if there's any damage etc.
But that kind of oil consumption is a bit scary so needs sorting for sure.

[FBJ]

Thanks for the comments so far

Ok, just had another look at the cams, the inlet say G4 (stamped in the end, It also has the following markings stamped in various places, EP71, C7, C2, D2, and CWC
THe other cam has KGG4 or KCG4, EP71, C1 & D1
Does that tell you anything, the cam followers have the number 27 stamped into them, are they stock?
Th cams are fitted to APE slotted sprockets.
FBJ

[Katgeezer]

That's interesting as the Yoshi cams in my 1325 are described as EP71 and they're stage2.....not sure what that means in the overall scheme of things mate. Stage2 to me always meant fast-road tune but not sure now..... This probably only confuses things more but may help someone with a different database to me.
I wonder if it's just an indication of different equivalent grinds as in EP71 is same as G4?? Not sure as I don't have all the specs to hand..I still think you'll be fine with standard guides tho'.

[Katgeezer]

Read that thread you started on OSS John, blimey they do get into it sometimes eh?!?!

Didn't realise it was so close on the margins with what I thought was a relatively mild cam profile upgrade.
That is of course why you ask Rupperton, cos he's a proper god

Sounds like a bit of a dear do for you mate. Do you need to replace the valve springs on the back of this info too??

[johnr]

ape springs arent too dear either. if i were changine the guides id go for the springs too just to be sure.

[FBJ]

I think the thread is going well on there, I didn;'t like it when that chap Ray said Roger never knew what he was on about. otherwise it's all good stuff.

Anyway I had a chat with Roger and sent the head of yesterday, having new guides fitted, all 16, seats all cut, valves refaced, new stem seals, and new ape valve springs. big wedge, but like I said to Flo these motors are all getting old, could spend £100 on a new head and have the same problem.

John

[Katgeezer]

Excellent, good luck mate.

[flufflonsdale]

Bloody yanks.....All mouth and trousers.Glad Flo is more understanding than my Mrs. Sarah still thinks a 1230 big bore, gas flowing ,new valves etc cost £200!! Its as high as I dare tell her.