Gixer1460

Have you got the 'good' cones or the 'bad' cones?...............LOL They all flow more air but some more than others. I'd stab at around 170-175 if std is 155 but that still be lean'ish. Are the carbs original to the bike as thats a possibility - someone has swopped carbs that don't have the same internals as the 850 types? If so - bigger jets is hit or miss - but you've nothing to lose by trying?

Are you in the States? If you are, and are using regular pump piss gas.............I wouldn't bother! It may make the pick up a bit punchier but the clattering from the engine knocking will soon wear thin!

How much free play / backlash is there at the twist grip? If none, it could be holding the throttle open..........or you've an air leak somewhere!

IMHO with an essentially stock engine, it should only need stock jets. An end can change shouldn't need much of a jetting change - even cams with stock inlet / exhaust won't change much as the breathing isn't much improved outside of the cylinders. But a K&N (say) in the airbox and a full exhaust in association with the cams will deffo benefit in good dyno set up.

Changing the plugs is one out of three - Leads rarely fail partially but not impossible. What about the coil - have you tried another? As they are supposed to fire two plugs, your's could be breaking down just enough to randomly fire either 1 or 4. All carbs should be set the same - only rarely do you up the mains in the centre pots due to heat build up

Nope - it's there to block the hole used in the factory to line bore the camshaft bearings. Lots of people myself included use them to feed additional oil to the cams - as std. it's a blank plug with a hex to tighten it

Well there is one suitable bolt / screw that's already started - 4No on the sides of the head! And if you are cooking the engine its just natures way of telling you to ride faster or get out of traffic LOL!

Blackened 1 & 4 does sort of point to plugs / leads / coil. The plugs may be salvageable but cleaning blackened or fuelled up plugs never seems to work - new plugs different story! If there are ANY electronics on the bike don't use D8ES plugs - you need DR8ES's ie. resistor plugs else the RF interference from the D8ES's will mess with everything. Of course swapping the carbs in the garage and having them rev clean ain't the same as out on the street and under load so it still could be a duff carb - but do the simple stuff first!

Not sure how successful JB weld will be as being primarily plastic it will insulate to a degree, also the tip of the sensor should ideally contact that which it is reading. Q - are the sensors both the same? Senders of that type are fairly slow response types and ideal for fluids - not air. Air temp sensors need to be fast response types or they are pointless. If it were me i'd drill and tap a bolt in the head and mount one sender there and the other in the sump - same mounting or direct into a thick bit of the casting ...............that'll give useful data.

8/10 - made a few corrections for you LOL!

You may want to sit down when you price up the valves and you'll still maybe have the same problem - the valve seats are worn out ie. the hole is too big due to the valve seat angle being cut too deep. I've never had a problem winding a plug into a head - cracked or not........ 2 or 3 threads up and the plug won't be seating so running it like that, you'd have to be deaf not to hear the compression escaping. Possibly its a crossed thread ..... or 2 - that'll stop a plug seating!

See other thread - come on, get the grey cells working its a 4 cylinder bike that fires one cylinder (power stroke) every 180 degrees - each coil fires every 360 degrees / once every revolution alternating between 1&4 and 2&3. Easy to tell if you get the DRL300 wrong pulse count - set box to 6000 - if it stutters at 3000, double the count. If it stutters at 6000 - its correct and if it doesn't stutter at 6000 then half the pulses as its trying to limit at 12000!

Single pick-up, 4 teeth, two revolutions = 8 pulses....................but the ecu / cdi / ign amp will condition that down to 4 pulses 180 degrees apart to run the coils wasted spark.

A M8 with a 1216 bandit used DJ'd 36 CV's and modded airbox and would do a tank after about 90 miles - now uses RS36's still breathing through the modded airbox and has more mid range, more top end power, smooth throttle response and is getting 120 - 130 miles to a tank, more if he's 'driving Miss Daisy'

These should help explain........

Piggy backing is correct otherwise the coils get no trigger signal normally! When piggy backed and limiter is activated, the white and blue wires get internally grounded to disrupt the sparks hence limiting the rpm.

Some more details would be useful - like what model GSXR? That looks like no GSXR i'm familiar with - the battery is too high, there is usually a seat front rail across the frame at that point that the seat base nose slides under to locate it, using lock at the rear to hold it. Also tank retainer looks moody! Whole picture looks more than a little unsafe to me!

Personally i'd say those valves and seats have been cut / lapped to death! The valves look pretty recessed and engines these days don't get 'coked up' with carbon like they used to - unless its burning oil ........ which with the low compression is a possibility. I think there is further investigation required - should have done a leak down test before you pulled the head - that would have pointed to valves or rings ........ wouldn't have stopped a strip down but you'd be fixing a known problem. BTW - that crack ain't it!

Wow - someone definitely has toooooo much time on their hands LOL!

That's a newey for me - never seen one - obs hence my comment, sort of same but different to a GSX though!

Not sure an aircooled operator can be used on an oiler - totally different operation - pull v's push. The GSXR 750 RR's has a RHS cable clutch but that's a rare / expensive option. Probably a 600 Blandit one may be the right length ....... but the usual trick when adding a lock-up to a hydraulic GSXR is adding a 6mm ball bearing to effectively lengthen the operation pin.

Inlet centres for Oil cooled or air cooled are 77 - 93 - 77....................water ones are 77 - 85 -77

77 - 93 - 77 from memory is correct factory spacing.

^^^ hundreds of years of experience speaking there LOL! But it's spot on advice ! With work, there are sometimes upto a second in just the chassis with no other power adjustments - just gotta find it.

Usually the tapers are ground not cut - not saying it can't be done but if not smooth and / or slightly incorrectly tapered, the rotor can spin. If you have access to a toolpost grinder - happy days!