CB900 Starter Clutch Upgrade to Yamaha R6 

Awesome! I have done both drilling new holes and slotting without using a machine shop. But to some, that may be a better option. Thanks for the input!

Thanks bud, glad to help.

John Snyder Awesome to hear and thanks for your input!

Glad to help :)

Yes, thank you. It was late and I was already fumbling for words, haha.

@@Exit39gmail Hey Scott I know this video is old but I have a CB 1100 F 1983 and it already has a bunch of holes in it and looks like I could just elongate the holes to match up with the new starter clutch it is not solid like the CB 900 any help would be appreciated thank you I have a picture if you’d like me to send

Aside from the sprag being a better design, more bolts lessen the torque load on the assembly. Think of it like a 4 lug nut wheel being swapped for a 5 or 6 lug. Personally, I have not see this design fail yet.

Yes, that would be the one.

@@Exit39gmail what is the correct part number for yamaha r6 bearing

The one I used is from a 2009. No aftermarket. According to another site I pulled this information from, these models use the 5SL-15590-00-00 starter clutch. 2003 R6 - YZFR6SRC STARTER 2003 YZFR6 - YZFR6R STARTER 2003 YZFR6 - YZFR6RC STARTER 2003 YZFR6 - YZFR6SR STARTER 2004 FZ6 - FZ600SS STARTER 2004 FZ6 - FZ600SSC STARTER 2004 YZF-R6 - YZFR6S STARTER 2004 YZF-R6 - YZFR6SC STARTER 2004 YZF-R6 - YZFR6SCS STARTER 2004 YZF-R6 - YZFR6SS STARTER 2005 FZ6 - FZ6ST STARTER 2005 FZ6 - FZS6T STARTER 2005 FZ6 - FZS6TC STARTER 2005 FZS6T_TC STARTER 2005 YZF-R6 - YZFR6T STARTER 2005 YZF-R6 - YZFR6TC STARTER 2006 FZ-6 - FZS6V STARTER 2006 FZ-6 - FZS6VC STARTER 2006 R6S - YZFR6SV STARTER 2006 R6S - YZFR6SVC STARTER 2007 FZ6 - FZS6W STARTER 2007 FZ6 - FZS6WC STARTER 2007 R6S - YZFR6SW STARTER 2007 R6S CA - YZFR6SWC STARTER 2008 FZ6 (BLACK METALLIC X) (CA ED.) - FZS6XBC STARTER 2008 FZ6 - FZS6XB STARTER 2008 FZ6 - FZS6XCB STARTER 2008 FZ6 - FZS6XCL STARTER 2008 FZ6 - FZS6XL STARTER 2008 R6S - YZFR6SXB STARTER 2008 R6S - YZFR6SXL STARTER 2008 R6S CA - YZFR6SXBC STARTER 2008 R6S CA - YZFR6SXLC STARTER 2008 YZF-R6S - YZFR6SXCB STARTER 2008 YZF-R6S - YZFR6SXCL STARTER 2009 FZ6 - FZS6YB STARTER 2009 FZ6 - FZS6YCB STARTER 2009 FZ6 - FZS6YCL STARTER 2009 FZ6 - FZS6YL STARTER 2009 FZ6R - FZ6RYB STARTER 2009 FZ6R - FZ6RYCB STARTER 2009 FZ6R - FZ6RYCL STARTER 2009 FZ6R - FZ6RYCW STARTER 2009 FZ6R - FZ6RYCY STARTER 2009 FZ6R - FZ6RYL STARTER 2009 FZ6R - FZ6RYW STARTER 2009 FZ6R - FZ6RYY STARTER 2009 YZFR6S - YZFR6SYB STARTER 2009 YZFR6S - YZFR6SYCB STARTER 2009 YZFR6S - YZFR6SYCL STARTER 2009 YZFR6S - YZFR6SYL STARTER 2010 FZ6R - FZ6RZB STARTER 2010 FZ6R - FZ6RZCL STARTER 2010 FZ6R - FZ6RZCR STARTER 2010 FZ6R - FZ6RZCW STARTER 2010 FZ6R - FZ6RZL STARTER 2010 FZ6R - FZ6RZR STARTER 2010 FZ6R - FZ6RZW STARTER 2010 FZ6RZB_CB STARTER 2011 FZ6R - FZ6RAB STARTER 2011 FZ6R - FZ6RACB STARTER 2011 FZ6R - FZ6RACO STARTER 2011 FZ6R - FZ6RAO STARTER 2012 FZ6R - FZ6RBCB STARTER 2012 FZ6R - FZ6RBCW STARTER 2012 FZ6R - FZ6RBW STARTER 2012 FZ6RBB_RBCB STARTER 2013 FZ6R - FZ6RDCL STARTER 2013 FZ6R - FZ6RDCW STARTER 2013 FZ6R - FZ6RDL STARTER 2013 FZ6R - FZ6RDW STARTER

Lorenzo, search down in the comments I replied to someone a few years ago with a list of compatible comparables and part numbers.

Hey John, thanks! I do want to make clear that I did not discover this. I only intended to offer my version and insight from another perspective. But I'm certainly glad it is of use! Anyway, I really did not measure the holes. Regarding "elongating the holes": @ 3:53 you can see when the three holes are lined up with the new assembly you could just elongate the holes by slotting them on the plate 'inward' so as to still use three attaching points. I chose to use all six. The best I can explain it is to measure the hole distances and inset from the edges on the R6 part, create a cardboard/paper template and using a compass transfer them to the Honda plate. I used a simple Harbor Freight drill press. Many of my tools are inexpensive as I'm not a shop and have little need for expensive tools that can be bashed on hour after hour, day after day and year after year. The hole size is not so critical and only needs to accommodate the bolt going through it and adequate seating area for the bolt head. The bolt size itself IS critical though. I hope some of this helps. It's been a while since I did this and I only did it once as it's documented here. I sold this bike shortly after this video.

Hi Scott! Good to hear from you mate! Your video was excellent by the way? After I sent my note last night - I figured a template out of stiff paper / cardboard would be the best route to take. I got new bolts from my Honda dealer which fit the Yam bearing body perfectly! My CB is going into the shop at Easter after the snow is gone to have a bank of refurbished carbs fitted (and also hopefully to have the new starter motor bits fitted at the same time only - if I get the holes drilled by then!). By the way have you seen the listings from 'headlesscycles' on US Ebay (from Oregon)? The trader has sold (sells) this conversion for $249? This seller states: "The key to making a long lasting unit is to surface grind each gear so it meets the sprag manufacturer's specification for diameter and surface finish. Without surface grinding, the worn out surface of a used gear race and the out of spec diameter could lead to premature failure. The stock starter gear race is ~.004" too large for the sprag and if it were used as-is then it is nearly impossible to get the sprag onto the gear race without disassembling the unit. Even after removing .004" from the race, the sprag is difficult to mount so a bevel is machines onto each gear race. This facilitates assembly and prevents damage to the sprag due to the application of excessive side force". Like you Scott, with a little practice I found the sprag easy to mount. Did you have any longevity problems by not removing the .004' from the race as stated in the sellers blurb above? and do you think this would cause any problems (excessive wear) in the long term? Thanks again Scott! Your assistance is much appreciated. Regards - John.

You can use a regular drill. I should have video'd that process. Maybe next time as I have a CB750 waiting in the wings with the new starter clutch on the bench. :)

Yes you will need to drop the oil. Also advisable to get rid of any oil remnants on the sprag threads, use the proper loctite cleaning agent before applying the loctite.

Definitely from an '09. Send me the microfiche your looking at, exit39@gmail.com.

Yes, it should work.

According to another site I pulled this information from, these models use the 5SL-15590-00-00 starter clutch. 2003 R6 - YZFR6SRC STARTER 2003 YZFR6 - YZFR6R STARTER 2003 YZFR6 - YZFR6RC STARTER 2003 YZFR6 - YZFR6SR STARTER 2004 FZ6 - FZ600SS STARTER 2004 FZ6 - FZ600SSC STARTER 2004 YZF-R6 - YZFR6S STARTER 2004 YZF-R6 - YZFR6SC STARTER 2004 YZF-R6 - YZFR6SCS STARTER 2004 YZF-R6 - YZFR6SS STARTER 2005 FZ6 - FZ6ST STARTER 2005 FZ6 - FZS6T STARTER 2005 FZ6 - FZS6TC STARTER 2005 FZS6T_TC STARTER 2005 YZF-R6 - YZFR6T STARTER 2005 YZF-R6 - YZFR6TC STARTER 2006 FZ-6 - FZS6V STARTER 2006 FZ-6 - FZS6VC STARTER 2006 R6S - YZFR6SV STARTER 2006 R6S - YZFR6SVC STARTER 2007 FZ6 - FZS6W STARTER 2007 FZ6 - FZS6WC STARTER 2007 R6S - YZFR6SW STARTER 2007 R6S CA - YZFR6SWC STARTER 2008 FZ6 (BLACK METALLIC X) (CA ED.) - FZS6XBC STARTER 2008 FZ6 - FZS6XB STARTER 2008 FZ6 - FZS6XCB STARTER 2008 FZ6 - FZS6XCL STARTER 2008 FZ6 - FZS6XL STARTER 2008 R6S - YZFR6SXB STARTER 2008 R6S - YZFR6SXL STARTER 2008 R6S CA - YZFR6SXBC STARTER 2008 R6S CA - YZFR6SXLC STARTER 2008 YZF-R6S - YZFR6SXCB STARTER 2008 YZF-R6S - YZFR6SXCL STARTER 2009 FZ6 - FZS6YB STARTER 2009 FZ6 - FZS6YCB STARTER 2009 FZ6 - FZS6YCL STARTER 2009 FZ6 - FZS6YL STARTER 2009 FZ6R - FZ6RYB STARTER 2009 FZ6R - FZ6RYCB STARTER 2009 FZ6R - FZ6RYCL STARTER 2009 FZ6R - FZ6RYCW STARTER 2009 FZ6R - FZ6RYCY STARTER 2009 FZ6R - FZ6RYL STARTER 2009 FZ6R - FZ6RYW STARTER 2009 FZ6R - FZ6RYY STARTER 2009 YZFR6S - YZFR6SYB STARTER 2009 YZFR6S - YZFR6SYCB STARTER 2009 YZFR6S - YZFR6SYCL STARTER 2009 YZFR6S - YZFR6SYL STARTER 2010 FZ6R - FZ6RZB STARTER 2010 FZ6R - FZ6RZCL STARTER 2010 FZ6R - FZ6RZCR STARTER 2010 FZ6R - FZ6RZCW STARTER 2010 FZ6R - FZ6RZL STARTER 2010 FZ6R - FZ6RZR STARTER 2010 FZ6R - FZ6RZW STARTER 2010 FZ6RZB_CB STARTER 2011 FZ6R - FZ6RAB STARTER 2011 FZ6R - FZ6RACB STARTER 2011 FZ6R - FZ6RACO STARTER 2011 FZ6R - FZ6RAO STARTER 2012 FZ6R - FZ6RBCB STARTER 2012 FZ6R - FZ6RBCW STARTER 2012 FZ6R - FZ6RBW STARTER 2012 FZ6RBB_RBCB STARTER 2013 FZ6R - FZ6RDCL STARTER 2013 FZ6R - FZ6RDCW STARTER 2013 FZ6R - FZ6RDL STARTER 2013 FZ6R - FZ6RDW STARTER

Most Excellent. Thank you.

which would be the cheapest? lol great info thanks

Salvatore Fezza Then go for it :)

Update: I dremaled the size of the gear shaft to fit the bearing

I found mine on Ebay through stores.ebay.com/depowersportsparts/ . Try them, if not some other salvage dealers.

@@goodlaughproductions2076 8mm×125, 1". I got them at Ace Hardware, but I'm sure most hardware stores will have them.

Id try tapping your wrench or ratchet with a hammer. Mine took quite a bit of force to break it free. Also, if your bike is on the stand chalk the wheel so it doesn't slip. P.S. its a lefty loosey righty tighty.

Justintm3 I was able to get it free with my impact drill. Thanks though

Blake Stone yea I was able to remove it with an impact drill. On another note, maybe you know the answer to this next question. That clutch gear spins freely counterclockwise when it is on crank. I tightened down those 3 bolts and added some loc tite. It seems that the crank is supposed to be rotating CCW, which would make me believe that the clutch gear should spin freely CW and provide resistance (ie turning the crankshaft) CCW. thoughts?

I would like to say yes as Honda interchanges parts vastly among models. As I don't have experience with that model though, double check your measurements and confirm with the unit you intend to purchase (spline diameter, teeth, etc). And by all means, report your findings back here to keep others in the know.

Aside from this modification, have you checked your fuel delivery? Spark plugs/wires? Coils? Etc? Just another though. I've had completely unrelated parts go bad on these older bikes when I'm working on something else. Happens a lot. Anyway, to check your starter clutch work, make certain that the pin on the back of the spark advancer is not damaged, broken or missing AND that it is lined up with the slot on the crankshaft. Check that the spacer is installed and correctly. Double check the torque on the bolts holding the starter clutch assembly together. As well, check the installation of driven gears (small gears to upper right of the main drive gear).

yeah all the gears are lined up fine, used all your torque specs properly. it turns over fine and did fire once but after that it has given me issues sparking again. new plugs, dyna coils, and new carbs that are clean and jetted pretty close to stock which is what I need. Did the clutch mod since I did have one bolt back out on my stock unit. Thinking it's electrical. The starter solenoid was sparking a bit and wondering if that would rob the plugs of enough spark to fire even though the starter motor is spinning fast enough to turn the bike over

flip the new bearing over to the other side.

The one I used is from a 2009. According to another site I pulled this information from, these models use the 5SL-15590-00-00 starter clutch. 2003 R6 - YZFR6SRC STARTER 2003 YZFR6 - YZFR6R STARTER 2003 YZFR6 - YZFR6RC STARTER 2003 YZFR6 - YZFR6SR STARTER 2004 FZ6 - FZ600SS STARTER 2004 FZ6 - FZ600SSC STARTER 2004 YZF-R6 - YZFR6S STARTER 2004 YZF-R6 - YZFR6SC STARTER 2004 YZF-R6 - YZFR6SCS STARTER 2004 YZF-R6 - YZFR6SS STARTER 2005 FZ6 - FZ6ST STARTER 2005 FZ6 - FZS6T STARTER 2005 FZ6 - FZS6TC STARTER 2005 FZS6T_TC STARTER 2005 YZF-R6 - YZFR6T STARTER 2005 YZF-R6 - YZFR6TC STARTER 2006 FZ-6 - FZS6V STARTER 2006 FZ-6 - FZS6VC STARTER 2006 R6S - YZFR6SV STARTER 2006 R6S - YZFR6SVC STARTER 2007 FZ6 - FZS6W STARTER 2007 FZ6 - FZS6WC STARTER 2007 R6S - YZFR6SW STARTER 2007 R6S CA - YZFR6SWC STARTER 2008 FZ6 (BLACK METALLIC X) (CA ED.) - FZS6XBC STARTER 2008 FZ6 - FZS6XB STARTER 2008 FZ6 - FZS6XCB STARTER 2008 FZ6 - FZS6XCL STARTER 2008 FZ6 - FZS6XL STARTER 2008 R6S - YZFR6SXB STARTER 2008 R6S - YZFR6SXL STARTER 2008 R6S CA - YZFR6SXBC STARTER 2008 R6S CA - YZFR6SXLC STARTER 2008 YZF-R6S - YZFR6SXCB STARTER 2008 YZF-R6S - YZFR6SXCL STARTER 2009 FZ6 - FZS6YB STARTER 2009 FZ6 - FZS6YCB STARTER 2009 FZ6 - FZS6YCL STARTER 2009 FZ6 - FZS6YL STARTER 2009 FZ6R - FZ6RYB STARTER 2009 FZ6R - FZ6RYCB STARTER 2009 FZ6R - FZ6RYCL STARTER 2009 FZ6R - FZ6RYCW STARTER 2009 FZ6R - FZ6RYCY STARTER 2009 FZ6R - FZ6RYL STARTER 2009 FZ6R - FZ6RYW STARTER 2009 FZ6R - FZ6RYY STARTER 2009 YZFR6S - YZFR6SYB STARTER 2009 YZFR6S - YZFR6SYCB STARTER 2009 YZFR6S - YZFR6SYCL STARTER 2009 YZFR6S - YZFR6SYL STARTER 2010 FZ6R - FZ6RZB STARTER 2010 FZ6R - FZ6RZCL STARTER 2010 FZ6R - FZ6RZCR STARTER 2010 FZ6R - FZ6RZCW STARTER 2010 FZ6R - FZ6RZL STARTER 2010 FZ6R - FZ6RZR STARTER 2010 FZ6R - FZ6RZW STARTER 2010 FZ6RZB_CB STARTER 2011 FZ6R - FZ6RAB STARTER 2011 FZ6R - FZ6RACB STARTER 2011 FZ6R - FZ6RACO STARTER 2011 FZ6R - FZ6RAO STARTER 2012 FZ6R - FZ6RBCB STARTER 2012 FZ6R - FZ6RBCW STARTER 2012 FZ6R - FZ6RBW STARTER 2012 FZ6RBB_RBCB STARTER 2013 FZ6R - FZ6RDCL STARTER 2013 FZ6R - FZ6RDCW STARTER 2013 FZ6R - FZ6RDL STARTER 2013 FZ6R - FZ6RDW STARTER

Yes. To reduce chances of them backing out again, thoroughly clean the threaded areas and apply thread locker. I'd advise at least removing the entire unit and checking for wear. The R6 swap is a fantastic upgrade though.

Mike Lowry Mine was from an 09. I'm sure other years will work. I listed a reference somewhere as a response here; look through the replies.

Hey Zak. I used an 09. Other years work due to same design, just not sure when this design was implemented.

Scott Chapman thanks!

This Mod works on my 1979 CB750k DOHC, should work on your's too.

Yes, FastLight61 used this process on his '81 CB900. My video is modifying my '82 CB900C. For your '79 CB750K it may be the same, but because I have not worked on one I don't want to say a definitive yes. I also have an '80 CB750F and it looks similar, but I have not performed this upgrade just yet.

Sorry man, I really don't know.