2008 VT750C Shadow Aero Will Not Go Past 50+ MPH?

[Gerry C]

I recently purchased a 2008 Honda VT750C Shadow Aero Trike that bogs down (cutting out) when attempting speeds exceeding 50-55mph. It is literally throttling down and stalling until the speed drops below this mark. I then have to have to downshift and work the throttle in order to keep it from shutting down. This whole thing literally scared me because traffic was moving at higher speeds and I thought I was going to get rear-ended.

So, I had it serviced and the Honda service technician found the TPS (throttle position sensor) shorted open as well as two vacuum leaks on two open ports. The carburetor was rebuilt, the TPS set to spec, spark plugs replaced, checked valve clearance, rode with timing light on - did not loose spark, checked flywheel to crank position and swapped computer out and was rechecked for malfunction. After this service it is now cutting out at 60-65mph according to the service shop. I have not yet been out on the trike to verify that is now cuts out at 60-65mph. If it is the case then I can live with that. Any thoughts and suggestions?

Today I heard from a gentleman in another forum and he believes the trike may have a rev or mph limiter installed. Apparently the technician where it was serviced was not aware of trike conversions with a rev or mph limiter installed. I understand the safety reasons for the limiter due to making high speed turns on a trike.

Does anyone out there have a good sense that the use of a rev - mph limiter is common practice in trike conversions? Is there a way for me to adjust the limiter so I may travel at slightly higher speeds? I appreciate any input from those with greater knowledge than I. Thanks.

 

[Jack Klarich]

First thing I would try is some Seafoam in the gas tank

It may help, make sure the throttle cables are not binding, see lf the throttle is opening all the way

As far as rev limiters, most modern bikes do have one

 

[rhino 2]

I recently purchased a 2008 Honda VT750C Shadow Aero Trike that bogs down (cutting out) when attempting speeds exceeding 50-55mph. It is literally throttling down and stalling until the speed drops below this mark. I then have to have to downshift and work the throttle in order to keep it from shutting down. This whole thing literally scared me because traffic was moving at higher speeds and I thought I was going to get rear-ended.

So, I had it serviced and the Honda service technician found the TPS (throttle position sensor) shorted open as well as two vacuum leaks on two open ports. The carburetor was rebuilt, the TPS set to spec, spark plugs replaced, checked valve clearance, rode with timing light on - did not loose spark, checked flywheel to crank position and swapped computer out and was rechecked for malfunction. After this service it is now cutting out at 60-65mph according to the service shop. I have not yet been out on the trike to verify that is now cuts out at 60-65mph. If it is the case then I can live with that. Any thoughts and suggestions?

Today I heard from a gentleman in another forum and he believes the trike may have a rev or mph limiter installed. Apparently the technician where it was serviced was not aware of trike conversions with a rev or mph limiter installed. I understand the safety reasons for the limiter due to making high speed turns on a trike.

Does anyone out there have a good sense that the use of a rev - mph limiter is common practice in trike conversions? Is there a way for me to adjust the limiter so I may travel at slightly higher speeds? I appreciate any input from those with greater knowledge than I. Thanks.

Re-Read my last post to you on your other post..

 

[Marc H]

If the tank is venting properly I would think fuel supply.Screen on the valve plugged,Partial blockage of the valve.If acceleration is junk maybe the diaprahms on the carbs.I bought a 83 shadow when i got back into riding and its topend was about where yours is and after doing some checking both diaprahms were busted.Thats probably not very common but it is a possibility.I have never heard of any kind of rev/speed limiter for trikes.Diagnos it like its a 2 wheeler.

 

[GoldWingrGreg]

Today I heard from a gentleman in another forum and he believes the trike may have a rev or mph limiter installed. Apparently the technician where it was serviced was not aware of trike conversions with a rev or mph limiter installed. I understand the safety reasons for the limiter due to making high speed turns on a trike.

Does anyone out there have a good sense that the use of a rev - mph limiter is common practice in trike conversions? Is there a way for me to adjust the limiter so I may travel at slightly higher speeds? I appreciate any input from those with greater knowledge than I. Thanks.

Call the trike manufacture and ask them. Most are very helpfull.