Fitting later model cams to a curvy.

[Blue_SV650S]

Ok I am getting impatient about trying to source just a set of pointy cams to put in my curvy to up its power … I was therefore thinking of buying a complete (and working) Pointy engine, robbing the cams etc and then putting the bits out of my curvy motor back into it to make a complete engine again … then sell it back on, hopefully for the greater part of what I paid (Disclosing it has had a cam change obviously!!).

Before I go down this route, does anyone know of any reasons why fitting early model cams to a later model bike might be detrimental to the running?!!? If it drops a couple of hp, who cares, but it will still run nicely right?!!?

Also so I don’t have to dredge through old posts, when fitting later cams to earlier bike do the timing marks stay the same?? I am talking inlet to inlet, exhaust to exhaust BTW, I know they are different if you swap inlet to exhaust etc.

[Biker Biggles]

Seems a bit drastic.Have you not been able to find a pointy engine that has done a big end?We keep hearing about people who forget to top up their oil and have this happen so there should be some available.

[Blue_SV650S]

Seems a bit drastic.Have you not been able to find a pointy engine that has done a big end?We keep hearing about people who forget to top up their oil and have this happen so there should be some available.

One of the first things that would be rogered if the engine died due to oil starvation is the cams ... so I rule them out instantly ...

With this in mind, I am looking for one that threw a rod or piston went etc or had a serious gearbox problem ... but there aren't many of them ;)

[northwind]

You could be surprised with the oil-loss engines, SV bottom ends tend to go pretty fast even when there's still some oil floating about... I've seen oil starved bottom ends with perfect tops. But it's a gamble...

The Vstrom engine has cams that are, I think, more restrictive than the curvy ones and that's otherwise an injected SV engine, right?

[northwind]

Oh yes... there's all sorts or dishonest ways to get a set of cams froma later model, I'm very proud of you all for not thinking of them ;)

[Blue_SV650S]

Oh yes... there's all sorts or dishonest ways to get a set of cams froma later model, I'm very proud of you all for not thinking of them ;)

If I could see the cams first then fine, but to take an unopened lump on and pay money and travel for it would be foolhardy ;)

yes unfortunately I am a honest person, at times I wish I wasn't :(

Rang Suzuki ... a set of NEW 05 cams are £400 ... so that's not an option ... I can buy a full working motor from a breakers for less than that ...

[northwind]

£400! From a K3 (exact same spec) I paid £126 for my intakes.

[skulpt]

HAHAHA......I let my SV run low on oil. The shell bearings melted and i scored the crank real bad. £450 for a 1500 mile engine. Lesson is, check your oil!

[johnnyrod]

Yep as Northy says, you only need the intakes, then use your old intakes on the exhaust side. This business of replacing them all, new buckets etc. just isn't necessary unless you've put loads of miles on it and started wearing things. You'll have to time the exhausts yourself but it isn't hard with some patience and there are reasonable to good photos on svrider.

[northwind]

Blue's going minitwinning so he's not allowed to do the in/in mod, he has to keep some sort of ex cam in the ex slot. Which is a shame ;)

[Blue_SV650S]

Blue's going minitwinning so he's not allowed to do the in/in mod, he has to keep some sort of ex cam in the ex slot. Which is a shame ;)


Indeed, to keep in the regs, I have swapped both like for like 8) I had to get some new shims, but all the gaps are now 1thou above minimum (wanted to run as tight as I sensibly could to get the max gain from new cams ... there is no point putting 1mm taller cams in then shimming out to max taking 0.1mm lift away again!! :D )

Ran it up today with the new cams in, runs dream ... took it for a bit of a blast up the local industrial estate :oops: and all seems well there. :smt035

Its not a comprehensive test, but as it showed no -ves signs, I am now prepared to take it to a trackday to test it for real!! 8)