Won't go above 60mph?!

Test: If possible (I know, a lack of tools), loosen the bolts (leave the front on but loose), raise the back of the fuel tank high enough to either remove the kink or get a longer piece of fuel line and replace it. Stuff some rags (a towel maybe) under the back of the tank with a bungee cord to hold it in place and test. Although I'd suggest a 90* petcock with that limited room.

BTW I put an electric fuel pump on my car a few years back. It came with the filter in the 1st pic. 5/16" outlet is fine..... but the 1/8" inlet due to the use of a threaded pipe fitting on the inlet RESTRICTED the pump rate! The float bowls would trickle full. Idled great, but could only go 'bout 60:banghead:.
I changed to the one in 2nd pic.... prob solved!
 

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I see your running VM carbs. Ask your mechanic what needles and jets are in them. He should know. I would read the carb guide or better yet have your mechanic read it. Some good information on jetting for the 650. The carbs could be the problem. Hope the fuel line works. A 90 petcock would cure that.
 
A quick and cheaper test would be to blast up to 70 mph in 4th gear, then upshift to 5th gear. That'll get you past the 'reversion' zone. If you find power returning at 70 mph and beyond, then it's probably reversion.

I can't even get up to 60mph period. I'll try and ride out 4th gear to the max and see what mph I can reach.

Also here's my intake;


I would like to upgrade to the uni-foam filter. BUT the way the ignition key hole is setup right next to the corner of the frame. If I use the uni filter I won't be able to fit my key into the ignition. I know the uni filter will fit no problem, but not my key. Lol

This wasn't my design or choosing, I bought the bike like this from the previous owner.
 
Just one petcock?
Test: If possible (I know, a lack of tools), loosen the bolts (leave the front on but loose), raise the back of the fuel tank high enough to either remove the kink or get a longer piece of fuel line and replace it. Stuff some rags (a towel maybe) under the back of the tank with a bungee cord to hold it in place and test. Although I'd suggest a 90* petcock with that limited room.

BTW I put an electric fuel pump on my car a few years back. It came with the filter in the 1st pic. 5/16" outlet is fine..... but the 1/8" inlet due to the use of a threaded pipe fitting on the inlet RESTRICTED the pump rate! The float bowls would trickle full. Idled great, but could only go 'bout 60:banghead:.
I changed to the one in 2nd pic.... prob solved!


Yes just the left side petcock has the kink.

Here's the right side petcock, which is free flowing no kinks;


I plan to get that kink fixed for sure, I'll get a longer fuel line and let it hang from the side a bit to get better room, and see if that clears the kink.
 
I see your running VM carbs. Ask your mechanic what needles and jets are in them. He should know. I would read the carb guide or better yet have your mechanic read it. Some good information on jetting for the 650. The carbs could be the problem. Hope the fuel line works. A 90 petcock would cure that.

I honestly didn't know it was VM carbs. I assumed it was stock, everything I got on the bike was from the previous owner. Only thing I did since I've owned it was a new ignition system, and a tune up.

Does my carbs have a particular model? So I can look up the carb guide for it, and hand it to my mechanic.

Fuel line is top of the list in getting fixed for sure.

I don't know what size or thread type petcock it is. Unless they're all the same thread type/size?
 
Damnn I was hoping I wouldn't have to get it relocated.

Don' jump too quick! Being VM's they'll probably work. But carbs work better with good flow, and those look like an afterthought.

Could also temporarily remove the air filters to see what it does (avoid dirty/sandy roads)...

:agree:

Hmmm I could ride it up/down my block. But I doubt I will reach up to 60mph though.

Leave them on till you get where you can get to speed, then stop where safe, remove, test, reinstall.
 
Don' jump too quick! Being VM's they'll probably work. But carbs work better with good flow, and those look like an afterthought.



:agree:



Leave them on till you get where you can get to speed, then stop where safe, remove, test, reinstall.


For sure, I'll bring that up to my mechanic and let him know.

I'll try it without the filters on the freeway, and see what happens. If the problem persists, then I'm back to square one right?
 
A common trick to prevent hose kinks is to fit a spring into the line, in the area of the bend.

Half-past naptime. Good luck...


What kind of spring? One big enough where it's snug inside the bend of the fuel line? What about corrosion of the spring being in the fuel?
 
Honestly, I'd be afraid to even start that thing up, what with unprotected fuel lines and plug wires resting right on top of the motor (what were they thinking???????). A motor gets hot you know, lol.
 
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