DB-03 Front Sprocket Warning

Cam · 01-18-2007, 05:38 PM

I don't know if this bike qualifies here or dirt, but hopefully the word will get out. I have seen pics of two of these DB-03's here.

Today, I pulled the sprocket cover to count the sprocket teeth for a gear down and I noticed the sprocket was loose. There was about 4mm of space.

The bolts were tight and the lock washer was ok, but the sprocket was not seating on the shoulder of the output shaft. Not good.

At the very least you could bugger up the spline on the shaft, at worse it could break the washer plate and bolts and lock the rear wheel up.

I don't know if this is a problem on all of the DB-03's, but if you own one you might want to take a look see.

ob1 · 01-18-2007, 06:28 PM

Hondas are designed with a little play in the sprocket/shaft fit, to allow for slght misalignment of the rear wheel. A solid fitting sprocket and misaligned rear wheel would result in a lot of wear on the front sprocket, less on the chain and rear sprocket.

4mm does sound like a lot of play, no doubt. When you replace the sprocket, that fit should improve.

Cam · 01-18-2007, 09:33 PM

Thanks for the info. The last Honda I owned was a '65 305 Dream, my first street bike, that was many years ago, but I don't remember any play in that one.

Is this a dirt bike thing? I can't imagine riding anything like this on the street. I would be concerned about the stresses on that lock plate. I think you could fit a 630 sprocket on this thing and still have play.

Just how much play does the average Honda have?

When you think you've seen it all, you haven't. Live and learn.

Thanks again.

'05 DB-03 Terminator
Rokon TB
Ural Retro
Harley Deluxe

ob1 · 01-18-2007, 10:41 PM

4mm seems a lot. See what kind of deflection you get with a replacement sprocket. Your present sprocket may be worn. Maybe someone with a brand new bike can check theirs.

Cant say that Ive measured the Honda deflection, and that would change with sprocket diameter, but I would guess 1-2 mm at most.

Cam · 01-18-2007, 11:09 PM

This is a brand new bike, it has about 10 miles on the clock. I measured the distance from the sprocket with it pushed back to the shoulder of the output shaft to the lock plate. 4mm.

The sprocket rides loose on the splined shaft, there is a lot of play in sprocket and splines, but my main concern is the 4mm thing.

Thanks.

'05 DB-03
Rokon TB
Ural Retro
Harley Deluxe

ob1 · 01-19-2007, 07:38 AM

My bike is a Honda XR200 with a Lifan 163FML2 engine. It uses the standard splined locking ring that rides in a groove in the shaft, and is bolted to the sprocket.

Sounds like your sprocket attachment is different, perhaps someone else will ring in with their observations.

frostbite · 01-19-2007, 07:49 AM

My Lifan has play on the countershaft sprocket as well, maybe 1 mm. 4mm seems really excessive. By comparison my Honda 300ex has equivalent play to my Lifan.

fatboy250 · 01-19-2007, 08:41 AM

Both of ours has more than I would have expected, but all the bolts are tight. Both have the 163FML engine.

FMYStreetRacer · 01-19-2007, 11:37 AM

i have the db-07a and mine walks around allot. probly more than 4mm. i put some grade 10.9 bolts on the retaining ring and let it fly.

Cam · 01-19-2007, 03:48 PM

Ok, did some research and here is the deal or at least what I was told. Honda spockets are designed to wobble a little. This is supposed to compensate for turning the bike in hard corners. When the rear wheel movement goes in either direction the chain will no longer be square and can wear or stretch unevenly or break. A 'little' wobble helps keep it square.

I guess some of them even have circlips holding the sprocket on.

What a 'little' is remains a mystery. I was told by a Honda guru at the dealer not to worry about it. They all do it and on a very low hp bike the 4mm should not be a problem. But I'll keep an eye on it.

liverchip · 01-19-2007, 05:28 PM

Just for reference, my Kazuma 110 quad has the same setup with a bit of wobble on the sprocket.

fatboy250 · 05-08-2007, 11:12 AM

Cam,
How's the DB-03 holding up?
Jason

01-18-2007, 05:38 PM	#1
Cam Join Date: Jan 2007 Posts: 18	DB-03 Front Sprocket Warning I don't know if this bike qualifies here or dirt, but hopefully the word will get out. I have seen pics of two of these DB-03's here. Today, I pulled the sprocket cover to count the sprocket teeth for a gear down and I noticed the sprocket was loose. There was about 4mm of space. The bolts were tight and the lock washer was ok, but the sprocket was not seating on the shoulder of the output shaft. Not good. At the very least you could bugger up the spline on the shaft, at worse it could break the washer plate and bolts and lock the rear wheel up. I don't know if this is a problem on all of the DB-03's, but if you own one you might want to take a look see.
	0

01-19-2007, 07:49 AM	#7
frostbite Join Date: May 2006 Location: Fredericton, NB, Canada Posts: 1,744	My Lifan has play on the countershaft sprocket as well, maybe 1 mm. 4mm seems really excessive. By comparison my Honda 300ex has equivalent play to my Lifan. __________________ Frostbite "The beatings will continue until moral improves"
	0

01-19-2007, 08:41 AM	#8
fatboy250 Join Date: Sep 2006 Location: COLUMBIA, SC Posts: 973	Both of ours has more than I would have expected, but all the bolts are tight. Both have the 163FML engine. __________________ 2008 Jonway MC-70-150 2007 Roketa DB-07B (RSM-200E) 2006 Roketa DB-07A (RSX-200E) 1995 Kawasaki Concours (ZG1000)
	0

01-19-2007, 05:28 PM	#11
liverchip Join Date: Nov 2006 Location: Mystery Spot Posts: 1,223	Just for reference, my Kazuma 110 quad has the same setup with a bit of wobble on the sprocket. __________________ 2009 XR650L Big Red Pig Tusk bar risers 2007 X-Moto(Jetmoto) GY250 --mods--- 15/40 sprockets UNI Pod Filter 2007 Shineray TMS 200XYi--Betsy Betsy Mods:______________________ Acerbis DHH headlight FMF Powercore pipe Uni Pod Filter
	0

05-08-2007, 11:12 AM	#12
fatboy250 Join Date: Sep 2006 Location: COLUMBIA, SC Posts: 973	Cam, How's the DB-03 holding up? Jason __________________ 2008 Jonway MC-70-150 2007 Roketa DB-07B (RSM-200E) 2006 Roketa DB-07A (RSX-200E) 1995 Kawasaki Concours (ZG1000)
	0

01-18-2007, 06:28 PM	#2
ob1 Join Date: Jul 2006 Posts: 499	Hondas are designed with a little play in the sprocket/shaft fit, to allow for slght misalignment of the rear wheel. A solid fitting sprocket and misaligned rear wheel would result in a lot of wear on the front sprocket, less on the chain and rear sprocket. 4mm does sound like a lot of play, no doubt. When you replace the sprocket, that fit should improve.
	0

01-18-2007, 09:33 PM	#3
Cam Join Date: Jan 2007 Posts: 18	Thanks for the info. The last Honda I owned was a '65 305 Dream, my first street bike, that was many years ago, but I don't remember any play in that one. Is this a dirt bike thing? I can't imagine riding anything like this on the street. I would be concerned about the stresses on that lock plate. I think you could fit a 630 sprocket on this thing and still have play. Just how much play does the average Honda have? When you think you've seen it all, you haven't. Live and learn. Thanks again. '05 DB-03 Terminator Rokon TB Ural Retro Harley Deluxe
	0

01-18-2007, 10:41 PM	#4
ob1 Join Date: Jul 2006 Posts: 499	4mm seems a lot. See what kind of deflection you get with a replacement sprocket. Your present sprocket may be worn. Maybe someone with a brand new bike can check theirs. Cant say that Ive measured the Honda deflection, and that would change with sprocket diameter, but I would guess 1-2 mm at most.
	0

01-18-2007, 11:09 PM	#5
Cam Join Date: Jan 2007 Posts: 18	This is a brand new bike, it has about 10 miles on the clock. I measured the distance from the sprocket with it pushed back to the shoulder of the output shaft to the lock plate. 4mm. The sprocket rides loose on the splined shaft, there is a lot of play in sprocket and splines, but my main concern is the 4mm thing. Thanks. '05 DB-03 Rokon TB Ural Retro Harley Deluxe
	0

01-19-2007, 07:38 AM	#6
ob1 Join Date: Jul 2006 Posts: 499	My bike is a Honda XR200 with a Lifan 163FML2 engine. It uses the standard splined locking ring that rides in a groove in the shaft, and is bolted to the sprocket. Sounds like your sprocket attachment is different, perhaps someone else will ring in with their observations.
	0

01-19-2007, 11:37 AM	#9
FMYStreetRacer Join Date: Nov 2006 Location: Ft. Myers, Fl. Posts: 416	i have the db-07a and mine walks around allot. probly more than 4mm. i put some grade 10.9 bolts on the retaining ring and let it fly.
	0

01-19-2007, 03:48 PM	#10
Cam Join Date: Jan 2007 Posts: 18	Ok, did some research and here is the deal or at least what I was told. Honda spockets are designed to wobble a little. This is supposed to compensate for turning the bike in hard corners. When the rear wheel movement goes in either direction the chain will no longer be square and can wear or stretch unevenly or break. A 'little' wobble helps keep it square. I guess some of them even have circlips holding the sprocket on. What a 'little' is remains a mystery. I was told by a Honda guru at the dealer not to worry about it. They all do it and on a very low hp bike the 4mm should not be a problem. But I'll keep an eye on it.
	0