1985 vt1100 - Honda Shadow Forums : Shadow Motorcycle Forum

Reply
 
LinkBack Thread Tools
Old 09-02-2012, 11:15 AM   #1 (permalink)
Member
 
Join Date: Aug 2012
Location: Tulare, California
Posts: 31
Default 1985 vt1100

I recently bought a 85 vt1100. It is cold starting but it does start. And runs good. But after it warms up it dies. Then doesn't want to start until it cools down.

Sent from my Zio using Motorcycle.com Free App
simonjmartinez is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 09-02-2012, 01:16 PM   #2 (permalink)
Member
 
Join Date: Aug 2011
Location: Sack-a-Tomatoes, CA, US
Posts: 796
Default

Mebbe the carbs need cleaning? Did it sit for a while before you got it? The 85/86 VT1100s were setup very lean and stock jets mean you almost always need to use the choke to start and until it is warmed up. Sounds like yours might be a little plugged. Can you keep it running after it is warmed up by using the choke? That would mean it has partially plugged jets = carb teardown/cleaning/rebuild. When I first got Lazarus, he had sat for a while, so I did this:

1. Drain the carb float chambers.
2. Pour in some fresh gas, blip tghe kill swithc to pump fresh fuel up into the carbs and let it sit overnight.
3. Drain the carbs.

Repeat until the gas coming out of the drains is clear and clean. Any greenish/yellowish color indicates jet corrosion 'cuz they are made from brass.

Another trick is to get a can of carb cleaner spray and after draining the carbs, spray up through the drain - that can cleanup stuff in the float chambers a bit. Again, repeat until the liquid coming out of the drains is clear. If there are still problems, the full teardown/clean/rebuild is probably necessary. Once you do go the rebuild route, replace the float needle valve and seat, gaskets, O-rings and adjust the float level. It would be a good idea to upgrade the jets a bit while you have everything opened up.

Rebuild kits - scroll down to the 1985-1986 kit:
Carb Kit Capital - Motorcycle Carb Parts

Jet calculator and kits:
Honda Jet Kits :: Honda 1100 cc Jet Kits :: Honda VT1100C Shadow 1985-1986 - Jet kits for Carburetors

Obviously, you will need a manual with diagrams and procedures. One tip - if at all possible, do not disconnect the cabs from each other, doing so almost always means a resync. If you are lucky, they are not too badly out of sync as is. You will prolly want to do a resync after getting it running better anyway, but why make more work for yourself at the start
__________________
Black Beast = '71 CB750
Lazarus = '86 VT1100C rescued from a salvage yard.
GrumpyOldMan is offline   Reply With Quote Quick reply to this message
Old 09-05-2012, 11:43 PM   #3 (permalink)
Member
 
Join Date: Aug 2012
Location: Tulare, California
Posts: 31
Default

Yeah after it warms up it idles good, not great. The cam pulse generator goes high. It reads 649 when its cold and like 1200 when the bike heats up. After that I can't even get a reading until it cools down

Sent from my Zio using Motorcycle.com Free App
simonjmartinez is offline   Reply With Quote Quick reply to this message
Old 09-06-2012, 02:19 PM   #4 (permalink)
Member
 
Join Date: Aug 2011
Location: Sack-a-Tomatoes, CA, US
Posts: 796
Default

By "goes high" what are you saying - RPMs or voltage output? Higher voltage should not be a prob. If it stops putting out anything, that would be a real problem. Replacements are only available from Salvage Yards and/or eBay unless you can find one from a different bike that will fit and puts out the same or similar voltage...
I would find an "experienced" Honda mechanic and ask if he knows of any other bikes that have a compatible pulse gen...
__________________
Black Beast = '71 CB750
Lazarus = '86 VT1100C rescued from a salvage yard.
GrumpyOldMan is offline   Reply With Quote Quick reply to this message
Old 09-06-2012, 03:47 PM   #5 (permalink)
Member
 
Join Date: Aug 2012
Location: Tulare, California
Posts: 31
Default

By high I mean resistance. I also have an 86 vt1100 that runs great but is STUCK in neutral. I tried rocking the bike and trying to shift, nothing. The clutch does not feel right but shouldn't it still shift even if the clutch is bad?

Sent from my Zio using Motorcycle.com Free App
simonjmartinez is offline   Reply With Quote Quick reply to this message
Old 09-06-2012, 04:25 PM   #6 (permalink)
Member
 
GadgetDad's Avatar
 
Join Date: Mar 2011
Location: Neptune, NJ
Posts: 208
Default

i had an 83 750 that had a bad pulse generator. when it heated up it would lose all power. I think i remember somebody explaining it as one of the wires in the coils broke, but still worked because they were lined up, until it heated up and expanded then they no longer lined up. Or something like that.
__________________

83 Shadow VT750C - SOLD
96 Shadow VT1100C
GadgetDad is offline   Reply With Quote Quick reply to this message
Old 09-06-2012, 04:37 PM   #7 (permalink)
Senior Member
 
Join Date: Nov 2008
Location: Visalia, CA
Posts: 5,377
Default

Quote:
Originally Posted by simonjmartinez View Post
Yeah after it warms up it idles good, not great. The cam pulse generator goes high. It reads 649 when its cold and like 1200 when the bike heats up. After that I can't even get a reading until it cools down

Sent from my Zio using Motorcycle.com Free App

Cam PG is bad, res should be about 400-450. Maybe more to the issue, but that generator is bad.
__________________
93 VT1100C Sleeper, VH Exhaust, Saddleman Seat, Baby Apes, Metzlers, 2mm sleeved and bored (1150cc),10.5:1 comp, Modified Heads, Valves, Cams, Adjustable Timing, Bored Carbs.
93gc40 is offline   Reply With Quote Quick reply to this message
Old 09-06-2012, 05:36 PM   #8 (permalink)
Member
 
Join Date: Aug 2011
Location: Sack-a-Tomatoes, CA, US
Posts: 796
Default

Since you have an '85 VT1100 and an '86 VT1100, you should be able to get one of them working and use the other for parts. My guess is that swapping out the bad cam pulse gen for a good one might be easier than rebuilding a broken/frozen tranny.
Yes, you should be able to get it into neutral even if the clutch is locked up by rolling the rear wheel a bit to take pressure off the shifting dogs.
__________________
Black Beast = '71 CB750
Lazarus = '86 VT1100C rescued from a salvage yard.
GrumpyOldMan is offline   Reply With Quote Quick reply to this message
Old 11-24-2012, 12:06 PM   #9 (permalink)
Junior Member
 
Join Date: Nov 2012
Location: sacramento
Posts: 22
Default

hey! Did you get your poor idling issue resolved ?.....hard to follow these threads sometimes. i have a 85 vt1100c and it runs great when its cold and then after about 10 minutes, like a light switch being flipped the rpm"s tumble and poor performance. I've shot a short blast of w d40 in the carb's (one at a time ) when this happens and noticed that the left carb doesn't respond at all but with the right carb the rpm's drop....as it should be! i can't find any vacume leaks, I've rebuilt the carbs in hopes of fixing this but i still have the same thing going on.
boxybike is offline   Reply With Quote Quick reply to this message
Old 12-17-2012, 11:08 PM   #10 (permalink)
Member
 
Join Date: Aug 2012
Location: Tulare, California
Posts: 31
Default

I found a bad cam pulse generator. I had to remove the engine to replace it. The bike slipped out of 2nd, and 3rd doesn't grab at all. So it is totally apart right now. Have to wait till after holidays to buy shift forks, shift drum, pulse generator and then see if that does the trick.
simonjmartinez is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Honda Shadow Forums : Shadow Motorcycle Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -4. The time now is 12:56 AM.



Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0
Garage Plus vBulletin Plugins by Drive Thru Online, Inc.
Motorcycle News, Videos and Reviews
Honda Grom Forum Harley Davidson Forum Honda 600RR Forum Kawasaki Forum Yamaha R6 Forum Yamaha FZ-09 Forum
1199 Panigale Forum Roadglide Forum Honda CBR1000 Forum Vulcan Forum Yamaha R1 Forum Yamaha R3 Forum
Ducati Monster Forum Harley Forums Honda CBR250R Forum ZX10R Forum Star Raider Forum Yamaha Viking Forum
Suzuki GSXR Forum V-Rod Forums Honda Shadow Forum Kawasaki Motorcycle Forum Star Warrior Forum KTM Duke 390 Forum
SV650 Forum BMW S1000RR Forum Honda Fury Forum Kawasaki Versys Forum Drag Racing Forum Ducati 899 Panigale Forum
Suzuki V-Strom BMW K1600 Triumph Forum Victory Forums Sportbikes BMW NineT Forum
Volusia Forum BMW F800 Forum Triumph 675 Forum MV Agusta Forum HD Street Forum Suzuki GW250 Forum
Yamaha Motorcycles Victory Gunner Forum Honda Vultus Forum HD LiveWire Forum Ninja H2 Forum Ducati Scrambler Forum Kawasaki Ninja 250SL Forum