Russ750ET

Could be either, or both bearing/gear wear then. Just had a quick look on CMS and it looks as though gears are still available, which is good.

Awesome cheers. That certainly sounds like a likely cause. I think I'll just go steady on her for the remainder of the summer and not do any excessive millage. But it looks like an engine out and full strip is on the cards, something to keep me busy over winter!

Yep. The noise only occurs when there's load on the engine when on the throttle, in top gear.

The 1980 GSX1100 has been slowly developing a whirring noise in 5th gear. Not horrendous but definitely there. Doesn't make the noise while coasting, only when on the throttle. Shifts through the gears absolutely fine. I'm thinking it's the 84,000 miles on the clock that may be the cause. Obviously I need to open it up and investigate, but I was wondering if anyone else has encountered this and what is likely the be the cause? Mainly so I can get an idea of what I'm getting into parts and price wise etc

16 - 42 on mine, with a 17'' rear wheel. It gets through the gears pretty quick! I'm probably going to try a 17 tooth front sprocket once the weathers cleared up

I've got the forks from my GSX1100ET stripped for a service. So figured now would be the time to have a fettle! Does anyone know of any set up tips, or improvements that can be made to these forks? As far as I can see they are in totally standard form, stock springs etc. These forks feature the air pressure adjustment, but I've never personally run them with any air in as they seemed unable to hold any. So I will replace the seals and O-rings in the air system while I'm at it.

Definitely sounds like a lean condition, which would suggest an air leak as Gix-er has stated. A good starting point regardless is to record your current carb settings. GSXR carbs have been used on your model with great success by many people over the years, so I'm sure someone can confirm if your jets and settings are in the ball park. The standard CV carbs can work well, I'm still working out some minor kinks with mine but I'm 90% there. Please note my engine is pretty highly modified and with a low restriction 4-1 pipe with very stubby silencer. So take this into consideration if you do decide to go the standard carb route with yours. You may not require such rich settings depending on your engine and exhaust set up.

Simoniz 'Matt Aluminium' Engine Enamel is good. Used on my 1100. Does have a slight shimmer to it but looks quite 'natural'. Done 1000 ish miles since painted and so far its holding up well https://www.getgeared.co.uk/simoniz-aluminium-engine-enamel-one-coat-tough-paint-spray-can-500ml?utm_source=google&utm_medium=ggshop&utm_campaign=ggshopbasic&gclid=CjwKCAjwzvX7BRAeEiwAsXExo1KM1AjA1PDuLGsSGfgobQq5n4PHXRz6UeUTWeD9NSrT3nJRPvrBuxoCogQQAvD_BwE

I've got this set up fitted to my 750ET. I don't believe its a specific kit for the bike. Just a generic oil cooler, with hoses I cut to length. The only specific piece is the replacement oil filter cover, which is a CNC made piece made from aluminium, with 2 NPT taper threads to attach the hose connections to. Unfortunately I wasn't the one to purchase it so I have no idea where it came from or who made it! The 750 doesn't have the oil sensor in the center of the cases, under the carbs like the 1100. So I think this is the only way you can do it on a 750, as the 1100 kits wont work. A crank breather may help stop your leaks

Good idea, thats got to be worth a go! Never thought about that possibility with the needles either, pretty sure I have a spare set of 5C32 needles so I will have to experiment

Made very good progress with the 750 and now have it running 99% perfect. The vacuum sync kit confirmed that the carbs were quite far out, and the bike ran noticeably better as the carbs came into balance. I spent quite a while getting them as perfect as possible. So to anyone else reading this with carb issues, balance your carbs first!! I have now changed back to 42.5 Pilot Jets, as it was virtually impossible to achieve any kind of sensible idle with the 45's. 2 turns out from closed seemed to achieve the highest idle and the low end response is pretty good. Now the interesting bit.... chatted to Grumpy Gary 1260, he suggested taping the filters as a way of proving if the carbs are generally too lean. So I wrapped a loop of tape around the base of each pod filter. What a difference! The flat spot is all but gone and the plug is a much healthier colour. Doing 5th gear roll ons from low speeds and the bike pulls clean through the rev range, with maybe the slightest small flat area that it quickly gets past and revs out nicely. The dilema I have now is do I ride with tape around my filters, or do I attempt to iron out the lean flat spot by playing with different settings? I've not found a richer needle the stock 5C32 for this carb. So I may have to bite the bullet and get a DynoJet kit at £138

I should have mentioned that I already have a Ledar air corrector kit fitted. Good to know about the filters, that will save me some cash!

I've not no, but I've just found it and read through it and it looks helpful! I'm getting a carb balancing kit tomorrow. I know I should have done that at the beginning, but I've been impatient and couldn't wait to ride the bike I'll get the carbs synced then follow the guide from there. I've also read that people don't seem to have much luck with the gauze style tapered cone filters like I'm running. I may ditch them for a set of foam filters instead, which will hopefully help with the flat spot.

Just had a quick look on the DynoJet UK site and it does appear as though they do them. Not in stock and £138 though! I'll have a play and see if I can improve it a little. But it's not the end of the world if it isnt 100% perfect. I was more concerned with it being potentially damaging, but the exhaust tip colour is a very dark brown, and the motor runs well so it doesn't suggest its dangerously lean? Thanks for your help

Yeah new plug, maybe had around 1 hours use. No this is after a 'roll into the drive and turn off' check. Standard jetting for a GSX750 is: 112.5 Main, 42.5 Pilot, 3.5 turns out on the fuel screw and a 5C32 Needle on the middle clip #3. So it's already a fair amount richer than standard. The bike rides well on the whole other than a flat spot at around 1/4-1/3 throttle. Could it be worth just putting more time on the plug, and performing some various RPM plug chops?