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When I pondered buying a Honda XR650R motorcycle, my BRP research spanned the web. Repeatedly, I unearthed references and horror stories about how tough it is to start these engines.  Forums were rife with starting and kicking rituals, choking methods and decompression lever habits. Add the mention of stock and aftermarket carburetors, suggestions on how to use the manual decompressor, descriptions of how best to use auto-decompression, you name it.  Eventually, one could get leery of approaching one of these critters or maybe buy a newer electric start KTM EXC. Common sense prevailed, after all, this is just a four-stroke motorcycle engine with 10:1 compression. I bought a BRP anyway.
 
So affected was I that when I completed a top-engine build that should start, I didn't expect the engine to start! (Objectively, some of this carried over from the several days of trying to start the BRP with a 90% cylinder leakage prior to the restoration of the top end.) The compression was spot on, valve and spark timing perfect, a new spark plug gapped properly, and preliminary carburetor settings "by the book".  The carburetor jetting, exhaust flow and choke were correct.  I had even check over the carburetor, though I would subsequently "blueprint" rebuild it. With a stock Keihin carburetor jetted to known norms that make sense for this engine and our region's altitude, everything pointed to an engine that would start...
 
I decided to use the same technique that always started my dual-carbureted '84 XR350R and '84 XR500R in sub-freezing weather or scorching summer heat. These are each motorcycles that many will never own because the "dual carburetors are junk!" 
 
This is good for the rest of us, as these four-valve thumpers are wonderful machines when tuned with the carbs sync'd properly! We can pick a nice bike up cheap. Just one example was an "as new", stored '84 XR500R that recently sold at a renown motorcycle auction for $2800. Wish I'd been there. These auctions usually generate a "fever" that drives prices to ridiculous heights, but not for a four-valve Honda thumper that has dual carburetors. Thanks to the internet, the word is out! 
 
After all the hype around BRPs and hard starting, I settled for a more rational approach—knowing that this engine should most certainly start well!  And you know what?  It did.
 
Cold, I can start this engine on the first or second kick when applying the choke correctly.  Once warm, as in this video, one kick ought to do it! Yet ahead, there's still the internet scuttlebutt and portent of "how bad these engines restart after laying them on their side". I've consciously avoided doing this so have no comment yet. I do have an approach for that, should the unplanned occasion present itself, and I bet it will work!
 


 
This video is an honest to goodness, candid start-up of the engine. My GoPro Chesty was on for the morning's second round of Acerbis tank road testing. The bike had been setting in the driveway for twenty minutes, minding its own business. I used the manual decompressor lever simply to tickle the piston past TDC on the compression stroke...Judge for yourself. This is a properly tuned Honda XR650R.

 
I'll make a point of filming a start-up with the dual-carbureted XR350R next time I ride it. Let's cross fingers that won't drive the price up on vintage dual-carbureted XRs!—Moses

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Thanks for the video Moses!

 

Thought I would share my cold start/dump the bike over and warm re-start procedures.  I've had 30 years of practice, including dual-carbs to work through in order to get this right.  I am average height at 5ft 8in, and at my age of 53, you can be certain I try to conserve energy for picking this pig up; not wasting it kicking at that foot lever!  For a little perspective I've been perfecting this procedure since my first BRP...the 1983 XR500R, then a 1987 XR600R (owned for 14 years until 2002), 2001 XR650R (owned since 2002 and still have it), and lastly, the new (for me) 2002 XR650R Dual-Sport BRP Road-Hog (BRRH!).

 

The following procedures may seem lengthy, but once you've learned them, the savings in personal energy and frustration will be worth it.  I can restart from any of the following situations in a matter of seconds.  Consistency is the key:

 

Rule #1:  Never apply throttle when trying to start...EVER!  The bike will flood and you will have to kick it forever, or "clear its throat" before it will start.

Rule #2:  Always refer to rule #1...never use the throttle in cold start, tip-over restart, or warm start.  Otherwise, kick, kick, kick...

Rule #3:  Always when cold starting, tip-over restarts, or just in doubt, CLEAR YOUR BRP's THROAT.  This means, turn off the fuel, open throttle wide-open, pull compression release, and easily run the kick starter through 5 to 10 kicks.  I don't like to call these kicks because that sounds like a lot of work.  Make these a casual run through with your butt on the seat...easy full length run-throughs with the kick starter.

 

Cold Starts:

  • Keep fuel off
  • Clear your BRP's Throat (Rule #3 above)
  • Turn up idle thumb screw (clockwise) 1/2 turn
  • Turn on fuel valve
  • Put up choke to full closed (lift up all the way to detent #2)
  • Slowly push kick starter down until it gets hard (this may take a couple half strokes), then pull compression release lever to get the piston just over top-dead-center (TDC), let go compression release, then push kick starter lever again until TDC, pull compression release and move kick starter so piston has just gone past TDC, let go of compression release.  Cylinder is primed with fuel at this point.
  • Now you are ready to start your BRP...DO NOT USE THROTTLE!  Let your kick starter lever return to top then give it a good, clean kick! (I usually do this without having to lift my butt off the seat, but when tired, put your kick stand down and do this procedure from on top of the pegs!) 
  • Your BRP should start...
  • Immediately lower your choke to level number one.  The only time my BRP's die on first kick is when I don't get the choke lowered quick enough...even in freezing weather!
  • If your bikes dies, leave choke on level 1, push the kick start through as before to load the cylinder with prime (using compression release as before at TDC), and give it a good, clean kick.  On very rare occasions I have to go back to full choke...very rare.
  • Leave choke on level 1 for no more than 20-30 seconds, move choke lever down to off position and use/blip the throttle to get her warmed up.  These things are little cold blooded but I don't like to let them warm up to long before riding (to keep from loading up).
  • Ride for a few minutes and turn off to check your oil (unless you did this the day before).  BRP's need to be really warm to get an accurate oil level reading.
  • After 10 to 20 minutes, go ahead and turn your idle screw back down (counter-clockwise) the 1/2 turn.  I prefer to leave idle a little high so I can get consistent and easy starts, especially when I lay the big girl down.

Restart Warm:

  • Prime kick starter slowly until piston is top-dead-center (TDC), pull compression release and push kick starter just past TDC, let go compression release and give it a good clean kick (DO NOT USE THROTTLE).  My BRP's almost always start first kick.
  • If your BRP doesn't start in 3 kicks, refer to rule #3, then redo this procedure.

Tip-Over/Flood Restart:

  •  I ALWAYS refer to rule #3 on tip-overs to make it easy on myself.  CLEAR THE BRP's THROAT with 10 kick starter run-throughs.  Again, these are easy run-throughs with the fuel off,  throttle wide open, and compression release lever pulled.
  • Turn on fuel, prime with kick starter to top-dead-center (TDC), pull compression release, push kick starter just past TDC, let go compression release and give it a good clean kick (DO NOT USE THROTTLE).  Almost always starts first kick.  After 3 attempts at prime/TDC, I refer to rule #3, CLEAR THE BRP'S THROAT procedure again.

Although all the above sounds complex, once you get it down, the consistent and easy starts are impressive. 

 

Hope this helps someone out there, whether a BRP veteran or a newbie BRP owner!

 

RSE BRP

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