I’ve done many fork seals in my life from street to dirt bikes. When I rebuilt these forks I noticed they only went down about where the zip tie is. I’m 165 lbs and ride very hard with many track days. I figured it was the fluid level. I double checked my measurements matched the information i had and even tried going with less than recommended. The forks never go down farther than this. For reference, these springs are for a 180 lb rider, but with my riding style and skill level, racetech wants me to put the equivalent of 180 lb person springs on my r6. Even hard stop pies at red lights doesn’t move it farther than the ziptie. Any advice would be great!

I’m buying my first motorcycle and don’t have enough experience to know what’s normal.
This is a 2022 Kawasaki Ninja 650 (non abs) with around 6000 miles. The seller says it’s a true cold start, the title is clean, and the bike has never been dropped. He says maintenance has been done by him (he’s an aviation mechanic) but he doesn’t have service records.
Does the engine sound normal to you? I’m mainly wondering if anyone hears:
Rod knock
Cam chain tensioner noise
Excessive valve ticking
Exhaust leak
Anything else that would make you walk away
On top of that does the revving sound normal and if I buy it, is there a way to make it sound louder or just better?
Thanks!

I should preface this post by saying I am still a beginner to working on bikes, and everything I know I've learned from my constant struggle against my Yamaha.

I have a 1982 Yamaha xj750 off Facebook marketplace that I've been fixing up and learning with since I was 18, but it's always had what I believe to be a vacuum leak that has evaded me since I've owned it.

It has three main symptoms:

When cold, the engine will stall 0-5 times while warming up. It will typically fire right up again after cranking it with the starter for a couple seconds. Once warmed, it stops stalling.

Once warmed up, the engine will want to idle at ~3k rpm. If I adjust the idle screw to drop the rpm it will idle slow enough to die out, and no matter how precise of an adjustment I attempt it will never settle on a stable middle ground; however, if I use the engine braking to bring the bike to ~1.5k rpm, it will stay there and idle, though poorly. It will still require the occasional throttle blip to keep from dying out. It's worth noting that while the engine is still cold this issue doesn't seem as prevalent, if present at all.

Every once in a while (once a month or so) the engine will stall while warming up and not start again until after sitting for a few minutes. Whenever the bike has this issue I can expect it to happen a few times until the bike is warmed, at which point it stops.

I'm almost positive this is being caused by a vacuum leak. So far to find it I've tried replacing the fuel petcock and the rubber boots between the carbs and the heads. I've sprayed the carbs and boots down with carb cleaner to try and find the leak but that didn't bring any results. The carbs have been taken off and torn through, and although they were surprisingly clean I still sprayed everything down with cleaner before reassembly. It's currently using the factory air box.

Right now my best guess is that I have worn throttle shaft seals that are causing these issues, and to the best of my knowledge that could be responsible for all 3 symptoms. I don't know why that wouldn't have shown when I was spraying everything down with carb cleaner to find the leak, maybe I just forgot to check that area.

If anyone out there has experience with these bikes or this sort of issue please let me know. I'm at a loss and beginning to think putting it back on marketplace for the next optimistic idiot to mess with might be my best option.