VT500 ,,Engine won't go over 7,ooo rpm

[chad]

Hi my friend has a VT500 for work (me i only like XS1100)
Anyway his VT will rev into the red when not under load
but while riding on the road it hits 7,000 revs and it feels exactly like a rev limiter has been hit

Any help advice ,,appreciated

Thinking main jets,,plugs,,?? any number of things really ??

[Vincent]

Why does he need to go into the red line You need more power to pull more weight, I would have thought most power on a VT would be lower down the rev range.

[Paddy Blake]

What has been done to the bike lately.Were the carbs off.
How long has it been like this or did it just happen.

Paddy.

[Paddy Blake]

[Trip]

Check the air lines / filter
____________________
Bike: Yamaha XJ600N Mileage: 28500 Miles Rider Mileage: Many Miles
CBT: PASSED Theory: PASSED Test: PASSED
Past-CG125 Present - Yamaha XJ600N Future - WHO KNOWS?

[bish777]

shit/water in carbs
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GSXR1100J

[Paddy Blake]

[Paddy Blake]

[chad]

Hi ,,sorry should have given more details

red line was just the gist of it as it ain't my bike i don't know what revs the red line is (think it's 9 thou tho ?? on that

he needs more than 7 thou coz any over taking manouvers become highly dangerouse and have to be timed and planned with precision and the fun is lost in riding the bike ,,i think it does 70 - 80 mph tops??

the bike has done 100 miles from NEW!! it had a slight drop and the owner never got back on it ,,he sold it to a guy that bought all the parts it needed including brand new petrol tank ,,but he never did finish it

my mate has put 1 new head on (BRAND NEW ) as a plug sheered off in the old one (must have been x threaded as it was so tight (removed the ceramic part,,used an easy out and that snapped in the plug as well so that did it for the old head basically )and that was my idea (the easy out) so i feel i owe him some help to get his bike running nice )

he cleaned the carbs out ,,put a new air filter in coz the old one was disintegrated into a thousand pieces (hmmmm that gets me thinkin !!!)

he has only changed 2 of the 4 spark plugs as he says they look brand new and spark ok ,,but no matter how much i tell him they might be breaking down underload (to me i'd pay the couple of quid for peace of mind anyway) he won't change the 2 others (maybe he deserves no help!!)

Thanks for replies anyway

[bish777]

make sure all the exhaust and inlet manifolds are on tight and not rotten and leaking.

Check the carbs are reassembled properly, the float heights are set correctly (youll need to find a manual to get the numbers) and the jet sizes are correct. Bare in mind if he has an aftermarket exhaust these will need replacing with different jets. really strip them apart and make sure debris from the old air filter arent blocking anything up.

Check the airbox is back on correctly, tightened up properly and not leaking. This can cause the bike to run like pants. Be sure the remnants of that old filter arent lingering anywhere. If you decide to ditch the aibox and run individual filters you will need much larger main jets for it to run properly (its much easier than it sounds tho !)
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GSXR1100J

[NSR Mick]