BMW K bikes (Bricks)


You are not connected. Please login or register

View previous topic View next topic Go down  Message [Page 1 of 1]


1Back to top Go down   Throttle Bodies Empty Throttle Bodies Sat Aug 04, 2018 10:03 pm

jahearne

jahearne
active member
active member
I was not able to sync the rear throttle body and found an air leak. When I first saw the intake manifolds, I thought there was an o-ring but I was mistaken. I haven’t found a source for these other than over priced NOS or used ones more dried out and cracked than mine. Any ideas?

    

2Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Sat Aug 04, 2018 11:59 pm

robmack

robmack
Life time member
Life time member
Are you talking about the TB bushings that are screwed to the engine block? Is this where the leak is occurring? If so, refit the bushings and use RTV gasket maker between the engine block and bushing.


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

3Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Sun Aug 05, 2018 3:20 am

jahearne

jahearne
active member
active member
It’s that simple? Alright, no problem. I’ll refit them with RTV. Thanks!


__________________________________________________
Throttle Bodies 1181537659 - John
    

4Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Sun Aug 05, 2018 4:06 am

charlie99

charlie99
VIP
VIP
whilst doing that , the head mount bushes harden at the head interface . and often distort especially at one end where the castings detour around the surface

smooth off the head mount surface of the rubbers  by rubbing them over a wet and dry covered firm flat surface until you get an even appearance

good luck


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
1987 k100rs ########   "Red"  - (red sports rs TWB style )
1989 K100rt #009637   "Black Betty"  (naked rt ala Nigel , now sporting an rs main fairing )
    

5Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Sun Aug 05, 2018 4:23 am

jahearne

jahearne
active member
active member
Right, I can clearly see where the old surface is squished over. Thanks for the tip!


__________________________________________________
Throttle Bodies 1181537659 - John
    

6Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Fri Aug 17, 2018 10:02 pm

jahearne

jahearne
active member
active member
That worked out well. I used 600 grit wet/dry sandpaper on a flat surface to clean up the mounting surface if the TB intake boots and a little RTV. Clean up the throttle bodies and everything bolted up. Thanks again for the advice!

However, the air box boots are dried up and cracked. Found a source for new ones:
https://www.ascycles.com/BMW-Motorcycle-Parts-Fiche/K100RS-1985-89?id=51752&catID=11&catname=Engine#PartsTable


__________________________________________________
Throttle Bodies 1181537659 - John
    

7Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Wed Sep 19, 2018 2:00 am

jahearne

jahearne
active member
active member
She fired right up on first attempt. Next week, sync throttle bodies, adjust throttle position, etc. Throttle Bodies 1aa55e10


__________________________________________________
Throttle Bodies 1181537659 - John
    

8Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Fri Oct 19, 2018 9:33 pm

jahearne

jahearne
active member
active member
Everything works great except I can't get the idle to rest on the idle stop screw. Idling around 1200 to 1400 rpm. It seems (after taking it apart for the 5th time) that the choke/fast idle is preventing the throttle from settling all the way down on the idle screw. The choke mechanism appears to be resting on the its stops, but the throttle shaft components are still resting on the fast idle cam just enough to crack it open up to 1200+ rpm. Easier to explain with some pictures, but I can barely get my hand in there... all this stuff sits between the throttle position switch and pressure regulator. At least I know what the problem is the next time I tear it apart.


__________________________________________________
Throttle Bodies 1181537659 - John
    

9Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Fri Oct 19, 2018 9:44 pm

duck

duck
Life time member
Life time member
Try loosening and adjusting the throttle position sensor. Sometimes that will hold the throttle open. Also check the positioning of the hose clamps below the TBs.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT
91 K1
93 K75S (K11 front end)
91 K75S (K1 front end)
14 Yamaha WR250R
98 Taxi Cab K1200RS
14 K1600GT
http://www.ClassicKBikes.com
    

10Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Fri Oct 19, 2018 10:45 pm

robmack

robmack
Life time member
Life time member
TB clamps should be positioned like this:

Throttle Bodies 101_Throttle%2520body%2520boot%2520clamp%2520locations

One thing I had to do on my actuator was this:

Throttle Bodies Ax058y


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

11Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Tue Nov 13, 2018 9:25 pm

jahearne

jahearne
active member
active member
Thanks for the tips. Triple checked all that over the last couple weeks. Clamps, Throttle Positions switch, etc. Quadruple checked it! Made sure the fast idle/choke wasn't interfering. Cables all have plenty of play. Re-sync'd the throttle bodies again and got it to idle a bit lower, but still idling around 1200 to 1300 rpm. 


When it's cold, the bike idles just fine, but as it warms up the idle goes up. Could be temperature related??? I ran into another K-bike enthusiast at the motorcycle club and he suggested the air intake sensor. Check connections, etc. Temperature gauge works well. Fan comes on while sitting in traffic. It all appears to be working as it should just idling too high.

I now have the tank off again, so I'll clean and dielectic grease all connections.


__________________________________________________
Throttle Bodies 1181537659 - John
    

12Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Tue Nov 13, 2018 10:25 pm

Laitch

Laitch
Life time member
Life time member
jahearne wrote:When it's cold, the bike idles just fine, but as it warms up the idle goes up. Could be temperature related???
Check the coolant temperature sensor. A test to check its operating range can be found within the Tech section of the site's Portal.

It will aid those who are helping you to troubleshoot if you take the time to put your bike's model and year of manufacture within the bike* box in your Profile. If you do that, your bike's model and year will show up with every post you make. Click the Profile tab at the top of this page. Parts and function can differ among models and model years.

Throttle Bodies Screen29


__________________________________________________
1995 K75 90,000 miles
    

13Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Tue Nov 13, 2018 10:37 pm

Point-Seven-five

Point-Seven-five
Life time member
Life time member
When you balanced the throttle bodies did you check how many turns out the air screws are from being lightly bottomed? 

I have never found a spec for the correct setting so I start with the reference throttle body air screw backed out 1 1/2 turns and balance the others to it.  If the idle is higher than I like when I'm done, I go back and set it for 1 1/4 or 1 turn and rebalance.  That usually gets the idle down to where I want it.

There is also an idle air bypass on the airflow sensor, but I leave it alone, mostly because it's a pain in the butt to get at.


__________________________________________________
Present: 1991 K100RS "Moby Brick Too"
 
Past:
1994 K75RT "Ilsa, She Wolf of the SS"
1988 K100RS SE "Special Ed"
1994 K75S "Cheetos"
1992 K100RS "Moby Brick" R.I.P.
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

14Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Wed Nov 14, 2018 2:13 pm

jahearne

jahearne
active member
active member
Laitch wrote:
jahearne wrote:When it's cold, the bike idles just fine, but as it warms up the idle goes up. Could be temperature related???
Check the coolant temperature sensor. A test to check its operating range can be found within the Tech section of the site's Portal.

It will aid those who are helping you to troubleshoot if you take the time to put your bike's model and year of manufacture within the bike* box in your Profile. If you do that, your bike's model and year will show up with every post you make. Click the Profile tab at the top of this page. Parts and function can differ among models and model years.

Throttle Bodies Screen29

Thanks, I'll check the temp sensor. My bike 89 K100RS SE is listed in the bike box, but not showing up.


__________________________________________________
Throttle Bodies 1181537659 - John
    

15Back to top Go down   Throttle Bodies Empty Re: Throttle Bodies Wed Nov 14, 2018 2:16 pm

jahearne

jahearne
active member
active member
Point-Seven-five wrote:When you balanced the throttle bodies did you check how many turns out the air screws are from being lightly bottomed? 

I have never found a spec for the correct setting so I start with the reference throttle body air screw backed out 1 1/2 turns and balance the others to it.  If the idle is higher than I like when I'm done, I go back and set it for 1 1/4 or 1 turn and rebalance.  That usually gets the idle down to where I want it.

There is also an idle air bypass on the airflow sensor, but I leave it alone, mostly because it's a pain in the butt to get at.

I started out at about 1 1/2 turns and ended up to right around 1 turn. I'll look into the air bypass, but do I really want to mess with it? Probably not since it's a pain to get to. Have to get to it while the bike is running I assume.


__________________________________________________
Throttle Bodies 1181537659 - John
    

Sponsored content


    

View previous topic View next topic Back to top  Message [Page 1 of 1]

Permissions in this forum:
You cannot reply to topics in this forum