Top speed 65mph...

[SpanishBob]

So my bike has an issue reaching high speeds. I can only get to 65mph on it in 4th. When a wind is blowing against me it slows me down. If I shift into 5th or 6th the bike starts slowing down and won't hold 65mph. It happened once I got my bike back from a shop. I've reach higher speeds on it with no problem but it really struggles to get to 65mph. Any ideas?

[mennobike]

Go back to the shop and make them fix what they broke 

Does it top out in all gears? how's the tach behaving?

[The Buddha]

Yea they likely ripped the diaphragm. Tiny tiny rip would do it, or even if they didn't seat it right.
Cool.
Buddha.

[SpanishBob]

I could go back to the shop but there is no way to prove they did it. It will go through all the gears and my tach looks fine. It stays at the normal rpm it was before. It just won't go past 65 So I'll take my carbs off and see what damage was done then. It wouldnt surprise me if they broke something since they also didn't tighten my spark plugs and tried to give me my bike back with no oil in it.

[i8ball]

OK if they gave back the bike oil free I think u have all the rights to argue with them, but I would never let a shop that can't remember oil to touch my bike if you think about it they might not tighten your wheel bolts or even make sure the chain is tight I would ask around on the site for a good machanic in your area.

[lucas]

You need a better mechanic.

[Daeouse]

Find a new mechanic!!! 

[fetor56]

ANY work u can possibly do on your bike yourself then do.You'll save money and learn,so IF mistakes are made guess whose to blame. 
I would still tell the motorcycle shop that at EVERY given opportunity your going to Poo Poo them........BIG POO'S....GODZILLA POO POO'S. 
Buy a workshop manual if u haven't already and still refer to the large number of utube videos on how to do different GS things.
Also ask here.

[lucas]

I agree.  I have never met a mechanic I can trust as well as myself.  I know exactly which corners I cut and which I didn't.  I can also keep detailed records of the torques I used, fluid levels, tire pressure, etc.

[SpanishBob]

So I was about to take the carbs off to look at the diaphragms and noticed something. I'm pretty sure in the picture below that tube had some sort of filter in it. So just for the heck of it I put some air filter foam in there and went for a ride. My throttle response was so much better. I could get to 65mph faster than before but she still isn't the same. So then I taped it over and took it for a spin. Again my throttle response was even better and I got to 65 faster. But I still can't get over 65. Before I take everything apart I was just checking to see if you guys knew anything about this.

For some reason the site isn't letting me upload pictures so I am posting links to them below.

https://drive.google.com/file/d/0BxK9YyLCf2x9bUNfTmxyNlNfems/view?usp=sharing

https://drive.google.com/file/d/0BxK9YyLCf2x9aTVrazdFZ2JaVFU/view?usp=sharing

[Suzuki Stevo]

EDIT: If you did that, Don't Kick Yourself In The Nut's, I'm sure you are aware of them then 

[fetor56]

I can understand Bob not being able to diagnose this....it's about the last thing u would expect from a paid "mechanic"
Almost as bad as some idiot who accidentally flipped his kill switch when removing his bikes cover,then spent 15mins trying to diagnose why said bike wouldn't start. 

[lucas]

The one time I paid someone to work on my GS they switched the wiring of the starter switch and kill switch.  It would run while I held the starter switch but die immediately afterwards.  That one was tricky to diagnose!!