gs1100 head work, 1168, 36 flatslides 1100e ready for rebuild. Have a few questions

[Reelinfeele]

Edited August 15, 2016 by Reelinfeele
So as you can see, Alice is sick.

[Reelinfeele]

Here is the plan. Valve job with port polish work. Measure bores and probably go with 1168 wiseco kit. 36 flatslides on the way. Also will be back cutting the trans. 

Do these photos look like guides or just seals? The problem is only on 2,3 and 4 intake. Exhaust side is nice and light brown. My problem with trans is popping out of 1st and 2nd gear. I know the clutch is adjusted good, bike is only good for 7k before popping out. I am running a Lockhart cooler. Are the 750 oil pump gears really necessary for a street bike that will never see a race track? Top end oiler? What cams would be best? 340? 310? The big question, is a gsxr or efe head really worth it or am I just as well to work with what I got? Also, if I do the wiseco's, what would be the proper clearance for the pistons? Or is this measurement supplied by wiseco or suzuki? Thanks guys.

[clairetoo]

I'd say the oil pump gears are a necessity as I found well worn cams in my average mileage EFE , top end oiling is not something to skimp on ! having said that , the top end oiling kits are a bit of a luxury on a road bike IMHO .

Check the selector drum for end float - something I learned in my early days of drag racing was to put a drop of red Loctite in both the drum bearing and the drum where it fit in the bearing during assembly - keeps it all in place .

[johnr]

youre only really going to know if its guides or seals when you get the valves out. dont be tempted with aftermarket valve seals, even with a famous well known tuning houses name on them. always fit genuine suzuki valve seals. otherwise, in 18 months to 2 years, you will be doing them again.  chances are it will just be valve seals.
750 pump gears are useful to have, these motors run on incredibly low oil pressure, so spinning the pump faster and thu providing a bit more volume, even if its not pressure, is useful, if youre running a cooler, it might help overcome the resistance of additional pipework and a cooler.
gearbox woes arent uncommon on thrashed or abused motors, but theyre a cheap fix, check the gears first before you replace anything. having the dogs undercut might help keep it in gear, although gentle treatment is equally good at prolonging life,

and using 2 detent springs when you rebuild it is a belt and braces solution.

[Jonboy]

Why are you polishing the ports? There seem to be two schools of thought regarding this, the first would be polished to give a slippery entrance/ exit to fuel charge and subsequent exit of spent gas. The second suggests that at least on the inlet, a slightly rough cast, as in how Suzuki intended, gives turbulence to the charge and this turbulence gives a better fuel mixture distribution when the charge enters the combustion chamber.

Maybe a good de coke and a deburr could be a simpler cheaper solution with potentially the same gain.....

[Gammaboy]

Modify the pickup so it feeds off the bottom of the sump, instead of 1" up from the bottom.

Fit a oil cooled GSXR selector detent spring - or two stockers.

Sounds like you're up for at least 2 new gears due to trashed dogs though

Edited August 17, 2016 by Gammaboy

[Sheep]

14 hours ago, Jonboy said:

Why are you polishing the ports? There seem to be two schools of thought regarding this, the first would be polished to give a slippery entrance/ exit to fuel charge and subsequent exit of spent gas. The second suggests that at least on the inlet, a slightly rough cast, as in how Suzuki intended, gives turbulence to the charge and this turbulence gives a better fuel mixture distribution when the charge enters the combustion chamber.

Maybe a good de coke and a deburr could be a simpler cheaper solution with potentially the same gain.....

Americans tried polishing the ports on British built Spitfires as they thought the rough casting was a sign of poor workmanship....after they f@cked up/seized the engines the Brits said 'told you so' ...the reason it had a rough finish was as Jonboy said,the better mix distribution....but this is vintage planes,not OSS mind you lol

[Reelinfeele]

So, then maybe just a 1166 kit and complete valve job. 36mm flatslides. No port and polish. Back cut trans and add gsxr detent spring. 

[johnr]

im no engine builder, or tuning expert, but ive found that the ports on these motors can have a fair few irregularities, not rough surfaces, but sudden changes in direction and casting irregularities. so i just blend them in. i dont polish or smooth the ports out, but if there are sharp angles in the ports or lines of casting joints i will clean em up.

[arnout]

2 hours ago, johnr said:

im no engine builder, or tuning expert, but ive found that the ports on these motors can have a fair few irregularities, not rough surfaces, but sudden changes in direction and casting irregularities. so i just blend them in. i dont polish or smooth the ports out, but if there are sharp angles in the ports or lines of casting joints i will clean em up.

Yup.. From what I've undertood about GSX cylinder heads is that the exhaust ports are difficult to improve (so leave as is), but the intake ports have many steps that can be removed with simple "hobby" tools to improve the flow.. Especially the transitions between the carbs and the ports are quite rough.. In part this has to do with the stock shape of the rubber manifolds that poorly line up with parts on either side.. But before modifying these (sanding drum bit on dremel) address the shape and location of the intake port first.. 99% of the case these are not concentric to the outside surface.. By scribing a concentric circle onto the protruding edge you have a guide for modifying the port.. (maintain a slight taper inwards). Copy the same circle to the rest of the ports trying to match the modified port..

With the new shape of the ports you have something to match the manifolds to.. (Repeat the shape matching with other ends of the rubbers fitted to the carbs, and then blend in the inner part for a smooth transition..) There may still be slight differences between the various rubbers (some ports are still a bit offset) so keep each manifold dedicated to each intake by marking them with the specific cyl. no. (using a white wall pen)..

Oh.. If you don't have a separate cylinder head to work with you may try your luck on a fitted head after stuffing the ports with rags as tightly as possible.. (use a vacuum cleaner to suck the swarf out before removing the rags after the work has been done..

Oh.. AFAIK the stock gearbox is already undercut (but perhaps not on all dogs)..

750 ratio oil pump gears are advisable when using hotter than stock cams and springs  (because of the extra strain on these parts), but not needed using stock cams/springs and if the lubrication circuit isn't blocked anywhere and a decent type of engine oil is used.. (The cams in the EFE engine in my Kat look terrible, but by using expensive syth. oil further deterioration seems to have stopped..)

Oh.. Always do a dry build (no rings) when fitting new pistons so you can determine the squish (piston deck to cyl. head surface clearance).. Using a different thickness base gasket is the easiest way to alter it.. (don't forget to include the head gasket thickness).. A small squish dimension makes for a stronger "swirl effect" and so better mixing of fuel and air and so better burn and efficiency.. Aim for 1.0 - 0.8 mm.. (Found in practice 0.6mm squish results in parts making contact..)

Oh.. Check the weight differences of the pistons as pistons in kits can vary considerable..! Making them equal would result in a smoother running engine (less vibes).. Some say getting under a 1 gram difference is vital, but I think 2 gram is good enough.. Don't forget the gudgeon pins! You can use possible weight difference here to compensate in part the difference with the pistons.. Removing aluminium from the bottom of the crown is how to equalize the piston weight.. 

 

Edited August 18, 2016 by arnout
extra stuff to ramble on about

[Reelinfeele]

The gears for the oil pump. Is it the gear thats on the outside of the pump? Are there 2 gears? Not really sure what to get for this mod. Thanks. 

[Arttu]

4 hours ago, Reelinfeele said:

The gears for the oil pump. Is it the gear thats on the outside of the pump? Are there 2 gears? Not really sure what to get for this mod. Thanks. 

Yep. The gear that's on pump's shaft and mating gear behind the clutch basket. You need GS750 gears or aftermarket "high volume gears" for GSX1100. Actually as far as I know also the aftermarket gears are genuine Suzuki parts for GS750...

[arnout]

3 hours ago, Arttu said:

Yep. The gear that's on pump's shaft and mating gear behind the clutch basket. You need GS750 gears or aftermarket "high volume gears" for GSX1100. Actually as far as I know also the aftermarket gears are genuine Suzuki parts for GS750...

Same gears (and partno.'s) on the GSX750..

GSX750 1980-1983 - GS750 1977-1979 :

GEAR, OIL PUMP DRIVEN (NT:29)
16331-45000

GEAR, OIL PUMP DRIVE (NT:38)
16321-45002

The price of these genuine parts from Suzuki have gone through the roof these last few years, so it might even be more cost effective to buy a complete 750 engine just for the gears..!

 

 

 

[johnr]

the ratio of the gears is only slightly different, i mean its not a huge difference if you look at them side by side, but obviously you need the pair (the one that sits on the back of the clutch basket-big hoe in the middle-left side gear in the pic above, and the one on the pump, right side above. make sure when you assemble it that the dogs on the larger gear are correctly engaged with the cutouts for them on the back of the clutch basket, failure to do so will cause you half an afternoon of head scratching and a large quantity of beer drunk till you realise why nothing wants to turn.... but dont expect masses of pressure, even with the uprated gears, roller crank gs/x engines run at the sort of oil pressure that will cause a gsxr owner to have a stress related  heart attack, these cranks dont need much pressure, at least not at the bottom end.

[Reelinfeele]

Found a set of gears. Pricey but I guess worth it. Transmission gets shipped monday. The spares I bought turned out to be exactly what I needed, so we will make one good transmission out of 3. Question regarding squish. I have read where squish should be .8 -1.0mm. I have never done a squish test. I have built a few motors, never had a problem. Where would I get a thicker base gasket a if I need one? Can I use multiple base gaskets? I am using the wiseco 1166 kit. Thanks for all your help. 

[Gixer1460]

The tighter you can get the squish the better it improves the burn but the tighter it gets the greater the risk of excess revs destroying the big ends from touching. Multiple base gaskets are ok copper, steel or paper options all good although paper can deform into the transfer galleries blocking up to 25% of their area. Personally I preferred to take the oil out of the block entirely and run external lines - no leaks and cooler oil IMO.

[arnout]

On ‎21‎-‎8‎-‎2016 at 3:22 AM, Reelinfeele said:

 Question regarding squish. I have read where squish should be .8 -1.0mm. I have never done a squish test. I have built a few motors, never had a problem. 

Well.. A GSX engine will run without a problem with all sorts of things and adjustments somewhere in the ballpark.. The way the bikes once left the factory was often also far from optimal using tolerances that would be unacceptable today..

Now you have the engine apart you are offered the chance to improve the stock setup by tweaking and modifying specific areas.. Doing is not "necessary" at all, but all tweaking will add up and pay off in extra power that is pretty cheap compared to buying bolt on performance parts..

On ‎21‎-‎8‎-‎2016 at 3:22 AM, Reelinfeele said:

 Where would I get a thicker base gasket a if I need one? Can I use multiple base gaskets?

Just Google Wiseco base gasket, or try http://www.suzukiperformancespares.co.uk/spares/base-gaskets/148/ or contact Debben or any other tuning (web)shop..

Or just make your own base gasket..

Stock EFE base gaskets are pretty good btw (fits earlier engines too)  And yes, you can stack gaskets if necessary..

Like Gixer1460 stated, don't use the stock paper base gaskets..

Edited August 22, 2016 by arnout

[Reelinfeele]

I received a Cometic base gasket from wiseco with the piston kit. 

[skelly]

As far as ports are concerned, 80 grit is fine on the inlets, ok to polish the exhausts tho.

If your not sure, let an expert do it.

Its very easy to take material from the wrong area and mess up the discharge coefficient.

If you are going to weigh the pistons, do it after you have set the ring gaps then weigh the pistons with rings, pins & clips.

You can sometimes jiggle half a gram here & there by swapping the pins around.

Skel