What is a valve starter?

[KA]

Bike was running rough and I replaced the plugs but nothing changed. Checked and found out that one cylinder was not firing. I notice that one of the valve starters looked to be missing parts. When I pulled it to where it seemed it should be the bike ran fine.

So what's this valve starter thing do?

[rockmeupto125]

What in the world are you talking about?

[KA]

They are on the back of the throttle body.

[ironmike]

The terminology you're using is somewhat confusing...

Try this; go to the shop manual (available on this site; link provided http://www.cbr1100xx.org/files/reference/CBR1100XX_Shop_Manual.pdf ) and review section 5 (all you wanted to know about F.I. on XXs). Find and identify the "valve starter" as depicted in any photograph, schematic, or line drawing and then get back to us. Hopefully, we'll be in a better position to help you out.

[KA]

That's what they call it in the manual and the parts list. Their terms not mine. See part #10 http://www.motosport.com/motorcycle/oem-parts/HONDA/1999/BLACKBIRD-_-CBR1100XX/THROTTLE-BODY

[runner]

From the Fireblade Site....

Starter Valve Synchronization and Plugs - Honda CBR 929RR / 954RR

Honda refers to the fuel injection throttle body synchronizing as Starter Valve Synchronization. Basically the purpose is to adjust throttle valve for fuel injection throats so that they pass as much fuel-air mixure as all the others (balancing the load by each piston). This balance will affect the response, smoothness, mileage, performance and running temperature of the engine.

I purchased Morgan's Carbtune II (4 column mechanical manometer). The scale is in cmHg (centimeters of mercury). The actual cmHg readings are not as critical as is the synchronizing of throttle bodies #2, #3, and #4 TO #1 ( #1's starter valve is fixed/non-adjustable). I also purchased Snap-On's TM-64 adjustment tool (recommended by member who first started the thread of Starter Valve Synch, DanDRR? Sorry can't remember who, maybe he'll chime in).

So. if anyone's interested, here's my details of how I did my spark plug replacement and Starter Valve Synchronization.

1. Set bike up on rear stand (optional)

2. Remove seat

3. Remove 2 front tank bolts and 1 rear tank bolt

4. Prop the tank up by string method, or I used tie downs extended from open ceiling joist in my basement to hold tank up by the (2) open bolt openings. I also removed the small vent line from under the tank to allow easier/more movement.

5. Remove the (8) screws around the upper airbox and the (2) screws in the middle. A pen light is very handy. Disconnect electrical connector and pull upper airbox cover off.

6. Remove air filter element, and start removing (6) philips head screws of the (2) pairs of velocity stacks. Remove velocity stacks.

7. Pull off (3) hoses on bottom portion of airbox and disconnect another electrical connector. Pull air box up and back to get passed air inlets, now flop the air box over the left side of bike (clutch side) watching for the flapper cable slack. I even used another tie down to support the airbox from above.

8. Pop each spark plug cap, I used leverage from large screwdriver and pryed it up. The plug caps are alot larger than I thought (maybe 4" in length). Pull electrical connection off cap. Remove all (4) caps and plugs, install new plugs, reinstall caps and electrical connectors. Make sure caps are all the way on and secure to spark plug.

Note: Morgan Carbtune recommends that you have everything in perfect working condition and any other work completed before adjusting throttle bodies, ie., new air filter, new plugs, etc.

9. Start removing the (4) vacuum bleed screws from just under the throttle bodies. They are both phillips head and 8mm hex head. Use the best method you can to gaining access to these screws, a magnetic screwdriver would be recommended (I dropped 3 of screws along with 3 of their washers, took awhile to locate and get them out). Flexible screwdriver would be ideal, although you still have to initially break the tight screw/bolt. Note: Also remove the PAIR valve hose at the reed valve and plug the reed valve nipple so to not give false vacuum readings?. Not too bad to get to.

10. Attach the (4) remote hoses for the Carbtune II, the hoses have brass adapters at the end that will thread back into the vacuum bleed locations. Use the hose to guide it to there, and spin the hose to help start threading the adapter (it's freakin tight in there). Make sure #1 bleed screw is #1 hose on Carbtune and so forth.

11. Start the bike and let it warm up to normal temperature, manual recommends using the throttle stop adjustment to raise the idling if necessary to keep bike running at idle and not stalling during synch adjustments. Note: FI light will blink 3 times, then go off, and blink 3 times, etc. This is because of the unplugged electrical connection of upper airbox.

12. After warmed up, document the starting readings of Carbtune. Mine were something like
#1-16cmHg, #2-19cmHg, #3-18.5cmHg, and #4-19.5cmHg.
Use the SnapOn TM-64 tool with a 7mm socket to adjust #2, #3, #4's starter valves to #1's settings. The starter valves are spring loaded and do not have a lock nut to loosen. The Morgan manual states acceptable synchronization is within 2cmHg of each cylinder. I got mine to equal out across the board at 16cmHg (just about perfect).


13. Adjust and wait for reading, gently blip the throttle to set the adjustment. Turn the starter valve clockwise to bring reading down. Adjust until all are equal or close to #1's reading. Turn off bike and reverse procedure.

Done, now throw away all the empty beer bottles!

Let the bike cool down before attempting to remove the Carbtune hoses/adapters, not only will the bike be hot but the adapters will be easier to unthread once cooled.

I have definately felt and heard the difference with my new plugs and synchronizing the starter valves. Idles smoother, crisp response, doesn't seem to vibrate as before - but, I haven't been able to test ride it yet (rain, rain, and more rain). I will reply with opinions of ride afterwards.

Feel free to correct anything I missed or wrong.

Later

[blackhawkxx]

Interesting.

[KA]

Thanks for the help.