Slight bog down around 6/7000rpm

These can be tricky so deserve a place all their own!

Slight bog down around 6/7000rpm

Postby Vtrinohio » Tue Sep 11, 2018 7:36 pm

Hey guys, I’m really close to finishing up my project. When I’m accelerating at around 6/7000 rpms, there is a slight lagging/bogging down. It seems like it is really trying to catch. Like it wants to go but something is just not quiet right. I did have to clean out rear carb jets as they were clogged. It starts great and idles great. I can advance throttle in neutral and don’t notice any kind of lagging. On a side note. How critical is it to have the drain hose running through the air box. I forgot to install the hose before I put the tank on.
Vtrinohio
 
Posts: 19
Joined: Sun May 31, 2015 10:58 am

Re: Slight bog down around 6/7000rpm

Postby squirrelman » Tue Sep 11, 2018 10:58 pm

to fix that i'd experiment with washers under the needle. no hose, no problem.
User avatar
squirrelman
 
Posts: 844
Joined: Wed Jul 18, 2012 1:57 pm
Location: Buffalo, NY USA

Re: Slight bog down around 6/7000rpm

Postby Vtrinohio » Wed Sep 12, 2018 8:45 am

A little more info. Took on a decent ride this morning. It’s actually around 5/6000 rpms where it hesitates a little. If I push through it, it seems ok? First gear seems normal all the way. Then I will shift to 2nd gear and at 5/6000 it will lag slightly. I’ve never ridden one of these so I’m not sure of the characteristics. I’m going mostly by feel. I see the rpms go all the way to 14 redline. I’m wanting to shift at around 7/8000. Maybe I’m not winding it up enough? Operator error? What is your thinking on the needles. Appreciate your help. Also I will post some pics shortly. This was a total rebuild. Just waiting on my vinyl numbers. I think you guys will like it.
Vtrinohio
 
Posts: 19
Joined: Sun May 31, 2015 10:58 am

Re: Slight bog down around 6/7000rpm

Postby squirrelman » Wed Sep 12, 2018 7:29 pm

lag isn't normal, but not so terribly annoying either. you could try jetting changes. i have a Dynojet kit in one of mine, and it's a real improvement over stock.

tuning carbs best requires knowledge of theory + experiments, sometimes many, to tune out one fault without introducing another.

when were those carbs last cleaned cleaned properly ? bike will have problems running if you haven't drained and flushed the fuel tank on an older bike.
User avatar
squirrelman
 
Posts: 844
Joined: Wed Jul 18, 2012 1:57 pm
Location: Buffalo, NY USA

Re: Slight bog down around 6/7000rpm

Postby Spoot5 » Mon Sep 17, 2018 5:42 pm

higher gears lets the rpm's climb at slower rate, so a flat spot becomes more noticeable.
that spot might be the needle not rising soon enough...as suggested, a shim\washer under the needle might resolve.
'90 VTR250 Interceptor / '98 VF750F Magna / '98 VTR1000F / '08 Ridgeline / Honda Racing Bicycle
CCS Mid-West #518 Am
User avatar
Spoot5
 
Posts: 93
Joined: Wed Oct 14, 2015 7:26 pm
Location: Southern WI

Re: Slight bog down around 6/7000rpm

Postby Vtrinohio » Tue Sep 18, 2018 7:04 pm

Appreciate the input, am going to dig in a little deeper. Will keep posted.
Vtrinohio
 
Posts: 19
Joined: Sun May 31, 2015 10:58 am

Re: Slight bog down around 6/7000rpm

Postby Vtrinohio » Sat Oct 13, 2018 6:45 pm

Hey Guys, I have a little more info on my problem that might help. I was just riding my fuel out to lower the level in the tank in preparation for pulling tank and while I was in the midrange of throttle and feeling the slight bog I reached over and thumbed the choke to half way and it immediately took off and felt normal. I thumb it off and it brings it back down? Also I do have an inline fuel filter which a guy suggested taking out. What do you think? Mark
Vtrinohio
 
Posts: 19
Joined: Sun May 31, 2015 10:58 am

Re: Slight bog down around 6/7000rpm

Postby squirrelman » Sun Oct 14, 2018 12:41 pm

think you need to clean carbs.

if you want to send them to an EXPERT professional for repair, please contact me.

assuming they just need cleaning, my regular rate to inspect, clean, adjust, replace O-rings, leak-test and synch VTR carbs is $110 +return shipping. my work is guaranteed for 30 days. Please drain and FLUSH your fuel tank b4 mounting carbs.

july 25-18 028.JPG
User avatar
squirrelman
 
Posts: 844
Joined: Wed Jul 18, 2012 1:57 pm
Location: Buffalo, NY USA

Re: Slight bog down around 6/7000rpm

Postby UK Keith » Tue Oct 30, 2018 3:56 pm

Sounds a bit like the way my VTZ behaved when the collector box was rusted through and blowing.
UK Keith
Donator
 
Posts: 338
Joined: Fri Jun 15, 2012 2:53 pm
Location: Hampshire, Southern England


Return to Fuel System

Who is online

Users browsing this forum: No registered users and 2 guests

cron