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Circuit breaker under battery compartment/close to rear shock ? accidentally knocked the kill switch ? - one of those I reckon . . . . with any luck

I got rid of mine years back, the forks are so rigid on the 1100m/n that flex can't be a problem. That bracket does act as a shield for the slider, against stones etc that could chip the chrome - I fitted plastic deflectors on mine, the late 750 forks on it now have no bracket and the mudguard is shaped to protect the slider - you'll be fine, that crappy mild steel rusts for a pastime, weighs 1 1/4 pounds too.

There's a few on here who've converted to efi - there's a member called Artu, who's done a fair few - if you look in the projects section you should see some conversions - I like the idea of efi too, could get some good gains I think. G1460 has done this too, with turbo just to speed things along ! There's definitely plenty of knowledge on here to help you. That's a decent tune you've done - 58mm stroke will give 1109cc with 78mm bore.

Good info by G1460 - my 1100N came with 40mm cv Mikuni carbs, being stubborn I've stuck with them as the bike evolved. They can work well, but in my experience only with an airbox, I had to give up when I dabbled without an airbox - lost loads of bottom-end and mid-range, even the top-end wasn't that good. With big bore kit fitted, some flow work and the Akrapovic system/Pipercross filter already fitted the carbs are working very well - I've got good bottom-end power , with a lift as 4k approaches, from there it's very quick and has winch like torque, top-end is very strong. If you want to use dual filters it's best not to use the 40's, if you don't like working with carbs - don't use 40's - I've got a couple of journals listing the various projects I've carried out on my bike, there's a lot in there about me fiddling with the carbs trying to get a factory type delivery - the bottom-end and early mid-range is the difficult bit - easier with a bigger engine though, but it still likes the airbox. If you're bike is putting out 112kw at the rear wheel I think someone has worked on the engine - the only time I've seen big hp from a std bike was when Superbike magazine tested an 1100K in 1989, it put out 143hp (about 107kw) - but according to the dyno it was revving to nearly 12000 revs, which the don't, but the tacho does show - so they'd got the rev signal feed wrong(this would muck up the hp calculation). If your dyno printout is to about 10800 revs and makes 112kw, you're a lucky man with a tuned bike !

Our engines have wide angled valves, unlike the latest stuff, this compromises chamber shape and piston crown shape, flatter is better - they use this to good advantage and run tight clearances . Modern heads are downdraught to help with cylinder filling, it also allows the whole valve circumference to be used, something that is much harder on a pretty horizontal inlet port. The cranks on modern stuff are much more compact and all components are reduced in weight...… you get the idea, there is a' BUT' though.... unlike modern stuff our old engines can be increased in capacity by levels far beyond hyper revving rockets - so the best way is to make the most of what you've got, or what can be more easily achieved. Our engines can make big torque and can be very entertaining on roads, even tracks - our bikes are like a big boned lass, they won't be good at marathons, but they're powerful over the shorter distances and have big ……..overhead cams ! (always nice) I'm pretty sure old GSXRs used an over reading tacho as part of the racy image thing Canamant !

If you're using a standard tacho they lie crazily, especially higher up - if you do a dyno run, or fit a good digital tacho, you'll see a big difference between real revs and those indicated on the standard unit (over 1000 revs). The standard cranks don't like to be over revved, even specially prepped ones crack through when asked to rev much beyond 11000 revs on a regular basis. These engines were raced a lot in the past and still are in classic classes, these engine's strengths and weaknesses are known - head design, crank strength and cooling will prevent what you're proposing. Modern engines are very different in design, port design is very different - there's loads to consider. Cams have to work as part of a package, you have to know the abilities of the other parts in order to design a cam that gets the best out of what you've got. I don't want to pee on your bonfire, but doing what you're proposing will just end up as a liability, engine failure isn't good... expensive and sometimes painful yes !

I might do that Jon, always good to make sure AFR is good, have a look at the shape of curve , seeing where improvements could be made - plus if I do go down the larger inlet valve route it'll be interesting how much is gained and where... then it'll be flatslides, directing more cool air to the airbox, getting an ally tank made and asking Jonny1Bump if he's got any CF bodywork ! - damn, thought I was done....

Just to put my mind at rest I've checked the valve clearances, any valve deflections should show up - I last set clearances before I accidentally advanced the cams and much to my relief they're the same - result ! There hadn't been any odd noises, or drop off in performance, but it was still best to check. With the cams properly set I've found that by lifting the needles a notch I've gained some more pick up as soon as the needle region starts to influence the mixture - carries on strongly too, not too different to the advanced power now, but it runs cooler, revs more readily and definitely pulls harder at the top, a lovely motor - just have to make sure I don't kick the crank position pointer/lad's ball knocking onto it/wife barging past it tutting, whilst I'm doing stuff in the future ...

Yep, pleased I found the reason Jon - wish I'd measured the p to valve clearance, would've shown something wasn't quite right too, I fitted new valve springs too, which probably helped avoid contact. I'm thinking about fitting larger inlet valves next, I'll definitely check the p to v clearance then. There's a company called G and S valves, who have 30mm inlet valves for M/N listed as the same weight as std 28.5's, so I could get more inlet charge into the cylinders and use std springs, so no additional wear on cams and losses due to harder springs...sounds like a plan, got some KibbleWhite guides on the shelf already...hmmm. I had the fuelling pretty rich for running in, I set the jetting after doing the oil and filter (and setting the cams - wrongly !).So it's only just recently I could feel the new power properly - it's enough to make me feel like fitting the steering damper again, getting crossed up by unexpected air time off bumps is a little too close to a proper shake now. The engine has lost some of it's low end grunt (compared with the 'advanced' set-up), but it's properly quick now - really impressed with the old girl - old GSXRs rock - will put a smile on your face and will want to kick other bikes in the nads … ! I haven't used green Loctite (haven't got any), I used permanent , but I did find out about doing one bolt at a time, oh the fun I had finding my new settings had moved before hand ! Thanks for the suggestions Jon

Thought I'd better share my error with everyone, I had been asking Jonny1Bump a few questions on his excellent build thread, but I don't want clog up his thread with my 'stuff'. My bike has a big bore kit fitted, ported head, de-shrouded valves etc. I spent loads of time trying to get everything as good as I could/was able. After 150 miles of piston ring/bore bedding in I changed the oil and filter - thought I'd check the cam timing at the same time.... found they had shifted from 105 centres to over 110 ! After finding true TDC I left the bike over-night and adjusted cams to 105 degrees the following day. I used the bike on a load of shortish trips over the next few months, was mega torquey, but during the hot weather in particular it was prone to pinking at the bottom end.... bugger ! Did the normal stuff to prevent pinking, but it didn't go completely - Jon said to retard the intake cam a few degrees, which should help. Anyway, it turns out that both cams were advanced by 10 degrees, that'll make it run hot !! - I think my crankshaft position pointer got snagged by someone going past the bike to the freezer - should've double checked TDC again... I will in the future, first time it's happened. I've since altered the cams and the engine feels less 'barrel chested' in delivery, but is smoother, revs harder and really shifts from 5k up - strong from 3k up , gets fruity at 4k, but the big torque and impressive power is from 5000 revs..... oh and it doesn't pink ! and obviously the cam sprockets hadn't shifted in the first place, lucky the pistons hadn't clipped the valves, must've been getting close - probably a good thing that major shove was available below 7000 revs at the time.

The broken off part off the rotor looks to be lurking under the forward pick-up with the green wire. Could've been worse Blue.

Pops certainly did ! - bet he was great to be around, not your average Japanese guy.....

I think it's G and S valves that list a load of products, including 1100M/N - I'm intrigued as they list the 30mm inlets at the same weight as standard 28.5mm ones..... I'm thinking about them for another project.

The 1100 m/n ones have a cable choke, remote idle speed like your 38's and the top carb spacer bracket is flat - just checked 750RK carbs on csmnl site, the rk carbs have odd diaphragm covers/ carb tops ……. dunno, just something I noticed about your 40's.

I tried a set-up a bit like that Clive - I think I used 155 mj, needles on bottom notch and 42.5 pilots - should be close enough to work with anyway. Those don't look like 1100 m/n 40mm carbs - are yours from a 750 rk ? 40 mm cv carbs can be/are mo fos to set-up...… I always see it as a personal challenge to make them work ! - they work better on my big bore and flowed motor, I kept the a.box as the power was much smoother with it in place.

If you want to advance the ignition timing you need to turn the plate anti - clockwise, then the pick-up/sensor meets the crank earlier - so is advanced compared to crank position. It's all relative to crank position. If you move the mounting plate clockwise the crank will rotate further before meeting the pick-up, so ignition will be retarded (compared to crank position). It's easy to think that moving clockwise is moving it forward, so advancing timing - but if you just consider it's all relative to crank position it all makes sense.

I've had several carbs that have caused headaches in the past (and fairly recently) and when all looks like it should work, with the f.valve shutting off the fuel, but doesn't - this has worked : Any slight residue on the sides of the valve seat will cause the float needle to snag slightly - the needle valve should be able to move freely, modern fuels are sods for leaving residue. Use a light polish to remove the crud, you know when you've done the job - the run up to the valve seat will be the nice brass colour again. Make sure the float needle is clean too - once done the needle should move freely up and down the valve seat assembly. I normally use a cotton bud to apply the polish (brasso works well), or cotton wrapped on the end of a cocktail stick, you can spin these with your fingers, or use a drill (which is what I use, just be gentle with it). When the carbs are at an angle, the floats don't exert as much force on the float needle (lop sided force acts on the pivot), so if the needle slightly resists movement, the needle won't shut the fuel off properly. It's always hard to visualise issues on the net, but doing this has prevented me from doing nasty stuff to the carbs for wasting hours of my time …...

An airbox does a number of jobs. Here's just a portion of them - The intake tract resonates due to the movement of the pistons and valves opening and closing (you are aware of this from the noise of open carbs) - the resonance can be used to aid flow, particularly at low/mid-range revs. The intake length has an impact on the resonance, so this can be used to boost various bits of the rev range - so helping overall power curve. There's a load of boring/interesting physics in play along the inlet tract, modern bikes make better of the airbox and intake system than our bikes, which were designed in the early days of airbox dynamics. A carb with a velocity stack will flow very well at high flow rates, but an engine with overlap will be boosted by the use of a tuned inlet length and airbox, not necessarily at peak, but it can be made to be a lot more effective throughout the rev range - as most bikes are ridden on the road and at a variety of throttle openings this is very helpful An airbox allows cooler, denser air to enter the carb, although it's only slightly helpful on most of our bikes - slingshots do try to vent some cool air to the rear of the airbox. An engine doesn't really 'draw' (as in suck) in air, the piston's downward movement causes a lowering of pressure within the cylinder and it's the higher atmospheric pressure that 'pushes' air through the carb and inlet , to cylinder- the velocity of air causes a lowering of pressure, which enables the carb to force fuel/fuel vapour through the jets, because the float bowl is at atmospheric pressure . I don't pretend to know everything, but I've tried to learn as much as I could over the years on how carbs work. I promise not to talk any more on this subject...….but some info into why airboxes can and do help seem to be needed.

Mine are like yours Blue - 1991/92 shim head 1100 inlet rubbers, for use with 40mm carbs. Numbered as you've said.

As Rene - a fresh engine with good piston ring sealing, good sealing valves etc should be good for around 140 hp, a used engine with unknown history ? something less than that.. do the valve clearances, people often don't like doing the shim heads as often, it's easier to do the screw and lock nut ones. If it's a good engine you should be pleased with the result, especially the second half of the rev range... good luck - Oily

Pretty sure B12 headers flow better than the 1400 - you can fit what cans you like on the 1400 headers and you don't gain much, the same can't be said of the 1156. They're very restrictive and some of the heaviest pipes going, makes the 1100 Slingshot std system feel light ! - the double walled, chromed pipes do look nice on the big retro though.

You're doing the right checks - if you know someone with a GSX1100F/GSXR1100 see if you can try their ignitor box - a ride will confirm if your box is restricted/faulty etc - the appearance of the missing 40% should be easily felt !! Oily

Have you had this engine running strongly before VJ ? or has the power only been less than great after this rebuild ? - I remember you had a piston/valve coming together on first build, did you use a GSX750F head on this or the 1100G one ? - trying to spot something for you … it's great when all works a treat but an utter pain in the arse when your hard work seems for nowt. My last big project was fitting a big bore kit, flowing the head and setting the cams etc - one problem I did find was that when I tightened the cam sprocket bolts, the sprocket moved - caused about 3 degrees of error - had to do them twice.

It's peaking early. but doesn't fall away completely after... what ignitor box are you using ? - although power peaks early it's revving to just over 11k - GSXR1127s hit the rev limiter at around 10,800 (true revs) ….. dunno what's happening. What's your exhaust like ? - even a poor design shouldn't kill the output that much . It's not like your bike is making loads of bottom end and losing at the top …. it looks like a 750 Inazuma dyno run, or Swiss market bike - it does look like one or two things are restricting it VJ.

I can see the Mikuni marking on the needles Kurf, but they're a sharper shape (richer initially) than my FactoryPro stage 3 ones. 150 mj should be close. You should get close using these guidelines from FactoryPro http://www.factorypro.com/tech/tech_tuning_procedures/tuning_carbtune,CV,lower_rpm_engines.html