Author Topic: Trying to revive a sleeping bike  (Read 548 times)

Offline The Mighty Gryphon

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Re: Trying to revive a sleeping bike
« Reply #25 on: November 21, 2022, 10:50:49 AM »
I wouldn't let a little cosmetic damage discourage me.  A lot of us have done repaints, and you aren't the first to find a lot of rusty frame under the tail cowl.  Fortunately, if you take your time, you can make some amazing improvements in the looks of your bike for a not exorbitant amount of money. 

The good news is that there are many here who have restored Bricks that were in pretty bad shape and documented their work here at Motobrick.com.  There isn't one job on these bikes that hasn't been documented somewhere here. 

The most important thing you need is some patience.  Take your time and our advice and you will have a machine to be proud of. 

It looks like you have a decent place to work, so it shouldn't be too hard to do this as a winter project.  I would strongly suggest that the first thing to do right now is to remove the bodywork and do a good clean on the frame and the wiring before the weather gets much colder.  Working on a dirty bike can really make even nice jobs suck. 

My favorite cleaner for this step is S100 which you can get at any Harley dealer and a lot of other motorcycle shops.  Once the frame is clean, keep it by your laundry tubs to clean parts as you remove them to be worked on.  Clean parts and a clean bike make this work a lot nicer.
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '91K100RS White/Blue
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'91 K100RS16V "Moby Brick Too"

Past:
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline Swampyankee

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  • Posts: 69
Re: Trying to revive a sleeping bike
« Reply #26 on: November 21, 2022, 01:57:57 PM »
I had the bike in the barn initially, but have since moved it to the garage under. The concrete floor, and stone walls for that matter, are a bit safer for working with fuel spills and the like. Plus, since my project cars are in there, it's where all the good tools are.   112350
  • Rhode Island
  • '86 K100RS
'65 Benelli Sprite
'73 Ossa SDR

Offline Laitch

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Re: Trying to revive a sleeping bike
« Reply #27 on: November 21, 2022, 02:04:00 PM »
I'm piecing together my understanding of the operating system on this bike.
This manual explains how it all works. You could have downloaded it from the site but I've saved you a step.
  • Along the Ridley in Vermont.
  • 1995 K75 83,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline Swampyankee

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Re: Trying to revive a sleeping bike
« Reply #28 on: November 21, 2022, 05:42:03 PM »
I did download it but I'm one of those that refer to the instructions as a last resort   :idunno:
  • Rhode Island
  • '86 K100RS
'65 Benelli Sprite
'73 Ossa SDR

Offline The Mighty Gryphon

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Re: Trying to revive a sleeping bike
« Reply #29 on: November 21, 2022, 05:45:03 PM »
I did download it but I'm one of those that refer to the instructions as a last resort   :idunno:

Probably not the optimum way to go through life. :idunno:
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '91K100RS White/Blue
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'91 K100RS16V "Moby Brick Too"

Past:
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline frankenduck

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Re: Trying to revive a sleeping bike
« Reply #30 on: November 21, 2022, 06:07:11 PM »
I did download it but I'm one of those that refer to the instructions as a last resort   :idunno:

Here's part of the owners manual you should read:

Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
New to K bikes? Click here.
K Bike Maintenance & Mods: Click here.
Buy parts here.

Offline Swampyankee

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Re: Trying to revive a sleeping bike
« Reply #31 on: November 22, 2022, 07:21:57 AM »
Well, I did read THAT part! The bike came with all the original owners and operation manuals, as well as warranty info, etc. and some receipts for maintenance and repairs, which I pored over. I also did read through past threads about these bikes and watched a bunch of Chris Harris videos on maintenance and repair before I even decided on a brick. I also went through the downloaded repair manual to familiarize myself with it, and continue to research info on diagnosing my bike's particular issues. But sometimes it's also good to tap into the collective knowledge of folks on forums like this.

So excuse me if I ask too many questions. Just looking for moral support as much as knowledge....
  • Rhode Island
  • '86 K100RS
'65 Benelli Sprite
'73 Ossa SDR

Offline Past-my-Prime

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Re: Trying to revive a sleeping bike
« Reply #32 on: November 22, 2022, 06:42:11 PM »
Ask away! No one HAS to answer. Other people might have the same question.   :thisplacewhack
  • North Shore of Lake Superior (in my garage)
  • BRICK: 1989 K75 RT - Rocinante; NON-BRICK: 2007 F650 GS Dakar - Betty Blue

Offline Swampyankee

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Re: Trying to revive a sleeping bike
« Reply #33 on: November 23, 2022, 08:49:30 AM »
This manual explains how it all works. You could have downloaded it from the site but I've saved you a step.

I assumed your link was to the Repair manual. Now that I'm on a computer and not the tiny screen of my phone, I see what you have provided here, thank you. I did not see that in the downloadable content, or did not recognize what it was. It provides the description of the operation of the FI system that I was looking for. As I go through the steps, I am leaning toward problems with the ignition/spark rather than the injection system. Given the amount of fuel I see being passed through, I would think the bike would start readily, even if it did run poorly and die from a too-rich mix, as long as a good strong spark was present. It does not want to pop even when initially cranked. The other thing is, when I pulled plugs and grounded them to the block checking for spark while cranking. It was pretty weak at best, and jumping across from the side of the center electrode to the base of the prong as opposed to jumping from tip to tip as it should. When I did have it running and idling, the removal of #2 plug wire made no change to the idle, which tells me #2 wasn't even firing.
I plan to check resistance of the coils and if ok, see if a new set of plugs would provide a solid spark. Hopefully I have the same easy fix as this guy. http://www.motobrick.com/index.php?topic=14612.0
Could corrosion of the hall sensor also be causing poor ignition response? As mentioned earlier, the bike has seen some weather.
  • Rhode Island
  • '86 K100RS
'65 Benelli Sprite
'73 Ossa SDR

Offline Laitch

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Re: Trying to revive a sleeping bike
« Reply #34 on: November 23, 2022, 09:26:09 AM »
Given the amount of fuel I see being passed through, I would think the bike would start readily, even if it did run poorly and die from a too-rich mix, as long as a good strong spark was present.
If the fuel/air ratio is too lopsided the mixture is unlikely to ignite regardless of spark.

Don't get into the Hall Sensor itself yet. First, clean all ground connections, including the main one under the tank, the hall sensor plug connection, the four-pin tank connection to the fuel pump, the Jetronic and ignition control unit plugs including their respective terminals, and the coil and plug wire terminals themselves unless they are new. The cleaner recommended by many here is DeoxIT D5, often found in music stores selling electronic instrument, sometimes sold in auto part stores and easily found online.

Brick engines are dependent upon good electrical connections. A disused Brick left out in the weather can be stubborn to start and if electrical connections are not thoroughly cleaned up, starting and running might occur but will likely be undependable.
  • Along the Ridley in Vermont.
  • 1995 K75 83,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline The Mighty Gryphon

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Re: Trying to revive a sleeping bike
« Reply #35 on: November 23, 2022, 09:37:00 AM »
I see that Laitch essentially said everything I have typed while I was typing, so let me just be an echo:

Considering that the bike has been out in the weather for a while, have you gone through and cleaned all the electrical connections?  There are a couple connectors under the tank that carry ignition signals from the Hall Sensors.  A little attention with Deoxit may help things along.  Also, if you haven't already, you should clean the ground connections, especially the one under the tank on the frame backbone.  You should be sure that the coil connections are clean and tight as well.  Over the years here, I've seen many bikes come back from the dead from cleaning the electrical connectors.

I think you are correct to be installing new spark plugs.  If you don't know how old the originals are, they are definitely worth the relatively small expense to be sure you have good ones.
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '91K100RS White/Blue
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'91 K100RS16V "Moby Brick Too"

Past:
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline frankenduck

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Re: Trying to revive a sleeping bike
« Reply #36 on: November 23, 2022, 09:54:04 AM »
If you suspect spark problems then the early K100 coils are not as reliable as the late coils.  Do measure the resistance across the coil terminals.



If you can find the newer coils on Ebay or wherever they are interchangeable with the early coils.

Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
New to K bikes? Click here.
K Bike Maintenance & Mods: Click here.
Buy parts here.

Offline Swampyankee

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  • Posts: 69
Re: Trying to revive a sleeping bike
« Reply #37 on: November 23, 2022, 11:06:18 AM »
I will check out coil resistance while I'm in there. I went through the same thing with the coil on my boat last summer.
I use Deoxit for cleaning scratchy pots on my guitars and music gear, and I've already used it on the 4 pin connectors for the fuel pump, so I'll check the other connections you mention. Looks like I'll be pulling the tank again. It'll be a bit heavier this time with the 3 gallons of fresh gas I put in. LOL
  • Rhode Island
  • '86 K100RS
'65 Benelli Sprite
'73 Ossa SDR

Offline frankenduck

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Re: Trying to revive a sleeping bike
« Reply #38 on: November 23, 2022, 11:09:30 AM »
If there's a decent amount of fuel in the tank then you'll want to lean it against a wall with the front pointing up to keep fuel from dripping out. Either that or put a cork/stopper in the rear outlet pipe.
Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
New to K bikes? Click here.
K Bike Maintenance & Mods: Click here.
Buy parts here.

Offline The Mighty Gryphon

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Re: Trying to revive a sleeping bike
« Reply #39 on: November 23, 2022, 11:51:30 AM »
Have you cleaned the ground connection on the left side of the transmission above the shifter?  The wire connected there is the main return from all the bike's electrical stuff to the negative terminal on the battery.  It's sort of in an unnoticed location, but still exposed to the elements.
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '91K100RS White/Blue
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'91 K100RS16V "Moby Brick Too"

Past:
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline Swampyankee

  • ^ Motobrick Curious
  • Posts: 69
Re: Trying to revive a sleeping bike
« Reply #40 on: November 23, 2022, 04:46:49 PM »
I did clean that one ehen I installed the new battery.
  • Rhode Island
  • '86 K100RS
'65 Benelli Sprite
'73 Ossa SDR

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