Gotta "funny noise"

[CROSSBOLT]

Just passed 17000 miles on a great running DT300i and I get this squalling sound at idle sometimes. Been riding a lot the last couple of 95 deg F days--about 300 miles total with several hours of 50-60 mph steady cruising. This noise would intermittently sound while waiting at a stoplight. Definitely engine speed related as it would vary with the throttle and would disappear if I "blipped" the throttle. The sound is like a worn bearing or a dry ball bearing. Two of my suspects are water pump or one-way clutch on the starter sprocket. What do YOU think?

Karl

[BettinANDlosing]

The drive belts start to make a little noise when they get old, kind of what your describing.

[Stig / Major Tom]

Hope a new belt fixes that for you Karl.
On my scoot that would be a lot simpler repair.
Maybe some new rollers and a clutch buff while Guido is in there?
Good luck with this...
Stig
(PS: I know a guy who knows a guy with a Kymco diagnostic tool, if you need it.)

[zombie]

I'm thinking variator boss. I've had a few wear to the point they would yell at me to swap them.

Open it up, and grab the var. You will know right away if it has any wobble.

There are also a set of needle bearings in the clutch.

If it were a crank bearing you would know it. The bike would sound like someone had a hammer, and was beating the engine.

Can't be tranny because it happens at idle, and there is no motion in the tranny then.

CVT or water pump but the pump would most likely leak.

[CROSSBOLT]

Zomb, I completely forgot about the needle bearings in the clutch! Gotta go check, RIGHT NOW!!

I am not really worried about engine bearings 'cause like you said, hammering. It's not a "heavy enough" sound. I ain't ruling out the drive belt, B & L, but I will check.....

Stig, I have been thinking about sliders and stuff....ya suppose that analyzer could tell me what the problem is? Yeah, right!

Karl

[BettinANDlosing]

Zomb, I completely forgot about the needle bearings in the clutch! Gotta go check, RIGHT NOW!!

I am not really worried about engine bearings 'cause like you said, hammering. It's not a "heavy enough" sound. I ain't ruling out the drive belt, B & L, but I will check.....

Stig, I have been thinking about sliders and stuff....ya suppose that analyzer could tell me what the problem is? Yeah, right!

Karl

I have noticed with my 250, the belt starts to sound bad well before it reaches the service limit. Kind of a rough, plastic friction noise. Hard to describe, but what you described sounds like it. Are you on your second belt by now?

[CROSSBOLT]

You guys got me to look into the CVT and you'll never guess what I found! Sunflower seeds! Filled up the intake breather "hose" and nearly shut off the intake COOLING air to the variator outer case. Here is what I found besides what I suspect is the cause: The front pulley sleeve bone dry. Still a good fit but no lube at all. Original belt missing pieces from the inside where the "teeth" are the biggest. The inner, metal case has a ball bearing to support the clutch bell and it is a slip fit to a sleeve behind the clutch bolt. The sleeve and the inner race showed fretting.

The needle roller bearing race looked really good as did the shaft. Cleaned out the variator and rollers. The rollers looked good and measured 20x12 mm and weighed 15 grams. The clutch shoes looked good and were de-glazed. The clutch bell looked great and got roughed up with some 200 grit emery cloth. The needle roller got greased as well as the sleeve. The bearing by the clutch got a dab of grease.  The belt or what was left was measured at 24 mm wide and outside roughly 1004 mm. 'Twas very hard to read inscription on the drive belt: Mitsubohi, Kymco, 23_00_LE_7-001. The lower dashes indicate characters illegible. Put everything back together and test rode to see if the problem still existed: it did not. Parked it and will order a new belt come Monday. This belt would still be in service with all its teeth has not the cooling air been blocked.

Now I gotta see what to do about a new belt. Hey, B & L, whatcha got for the DT300i? Dee-dee, where did you get your belt? By the way, found something missing when searching Kymco parts diagrams for water pump bearings: water pump bearings! Not shown on the parts diagrams!

Karl

[BettinANDlosing]

You guys got me to look into the CVT and you'll never guess what I found! Sunflower seeds! Filled up the intake breather "hose" and nearly shut off the intake COOLING air to the variator outer case. Here is what I found besides what I suspect is the cause: The front pulley sleeve bone dry. Still a good fit but no lube at all. Original belt missing pieces from the inside where the "teeth" are the biggest. The inner, metal case has a ball bearing to support the clutch bell and it is a slip fit to a sleeve behind the clutch bolt. The sleeve and the inner race showed fretting.

The needle roller bearing race looked really good as did the shaft. Cleaned out the variator and rollers. The rollers looked good and measured 20x12 mm and weighed 15 grams. The clutch shoes looked good and were de-glazed. The clutch bell looked great and got roughed up with some 200 grit emery cloth. The needle roller got greased as well as the sleeve. The bearing by the clutch got a dab of grease.  The belt or what was left was measured at 24 mm wide and outside roughly 1004 mm. 'Twas very hard to read inscription on the drive belt: Mitsubohi, Kymco, 23_00_LE_7-001. The lower dashes indicate characters illegible. Put everything back together and test rode to see if the problem still existed: it did not. Parked it and will order a new belt come Monday. This belt would still be in service with all its teeth has not the cooling air been blocked.

Now I gotta see what to do about a new belt. Hey, B & L, whatcha got for the DT300i? Dee-dee, where did you get your belt? By the way, found something missing when searching Kymco parts diagrams for water pump bearings: water pump bearings! Not shown on the parts diagrams!

Karl

Good find cross bolt, one note: the variator boss is dry lubed, idk the science behind it but the brass sleeve pressed into the movable half of the variator is "self lubricating". I do tend to put a tiny dab of malossi MRG grease on, but I'm pretty sure it just flings off in a mile or two. I'll check on the belt, not too many 300's here so I don't believe we have it in stock but I'll get you a price, would be about a week from key co to us then a day or two usps to your door. Damn mice!!! If your bike sits out a lot, my dad has a huge problem with mice in California and the surround the cars with a sheet metal wall and it keeps them out pretty good.

[de dee]

300i downtown belt   I order from      powersportswarehouse.com   cost   $98.99    they are located near charlotte NC., so fast delivery,  could you measure the belt when it arrives,  I have got belts 1004 mm.  to 1010 mm. 25.5 wide to 24 mm.  on my 4 th belt in my stock for a spare, the first belt looks like new with 30,000 km. on it,

[CROSSBOLT]

Thanks, guys! That was fast! De dee, I used your link and called those at Power Sports Whse but I could not get a real person on the phone. Anyway, I left a message and probably will order from them IF they have it in stock.....otherwise I'll get it from B & L. The local dealers have NOTHING in stock and want an arm and a leg for "handling & shipping".

Karl

[zombie]

Note to self...
Banana in tailpipe "Old Hat".

Sunflower seeds in CVT "New School".

B&L is correct on the drive boss. The sleeve in the Var. is silica bronze, and it is self lubing.
I just lube the crankshaft to prevent rust, and whatever is on my fingers is enough to "prime" the drive boss. Just so it is slick to start the process.

[BettinANDlosing]

Thanks, guys! That was fast! De dee, I used your link and called those at Power Sports Whse but I could not get a real person on the phone. Anyway, I left a message and probably will order from them IF they have it in stock.....otherwise I'll get it from B & L. The local dealers have NOTHING in stock and want an arm and a leg for "handling & shipping".

Karl

I can't even touch that power sports $98 belt, we have them listed at $110. I'm not sure how that company is making any money selling those at $98, but I can tell you they most likely skimp on customer service. I can do $110 and stuff it in a flat rate box for $6, and there are real people you can talk to if you like haha. Like I said, it would be coming from SC kymco warehouse, so it would be 7-10 days to your door.

[CROSSBOLT]

It really takes them 7-10 days?

Karl

[zombie]

Or three months. Depends on the mood.

[BettinANDlosing]

Yeah I don't know why, there parts shipping is expensive and slow, I can ship stuff usps for cheap and fast.