HELP!!! Possible Bent Countershaft?! (TT250)

[PNWDualRider]

Hey guys, I got home from one evening and noticed my chain was loose. I tightened it to 15mm of free play exactly, and now the chain has a grinding sound twice per rotation of the wheel. I looked all over to see where it might be grinding and I am wondering what I should do. I know I have not over tightened the chain as it clearly has 15mm maybe even 16mm of free play which the manual says is what you need. What else might be the problem?? Help please as I am leaving on an adventure ride this Thursday... Thanks in advance.

[PNWDualRider]

Here is a video of the sound for reference... https://youtu.be/zEtLk3U0eR4

[Azhule]

Did you take the front sprocket cover off yet? Grab a Hockey Puck and a Jack, set it on the right rear area on the frame (near the rear shock usually) to raise the rear tire off the ground, this way you can spin the tire while looking at everything while it's spinning.

Also how many teeth on each sprocket and how many links in the chain?

[PNWDualRider]

UPDATE*** I took off the sprocket cover to see if I could see anything wobble and I shifted through some gears and it seems to have disappeared which leads me to believe it might be a transmission thing. I wonder if I broke some teeth off the sprockets in the gearbox because when accelerating from a stop, it seems like it has to grind and then catch in first gear to get going...

[BlackBike]

UPDATE*** I took off the sprocket cover to see if I could see anything wobble and I shifted through some gears and it seems to have disappeared which leads me to believe it might be a transmission thing. I wonder if I broke some teeth off the sprockets in the gearbox because when accelerating from a stop, it seems like it has to grind and then catch in first gear to get going...

Next, inspect the dumped oil for fod.

[PNWDualRider]

Next, inspect the dumped oil for fod.

Sounds good. I'll do a full oil change and inspect oil. Am I looking for anything in particular or just chunks of metal? Thank you all for the help so far. I'm willing to do the work if I know what I am doing. Love you guys lol

[kohburn]

broken gear teeth will give you chunks, instead of shavings.

[PNWDualRider]

UPDATE** I changed the oil and cleaned the oil screen and among the many metal shavings, there weren't any chunks. I fired up the bike and let it run a bit until it studdered then died. Would not turn over. The first thing that popped into my mind was that I didn't put enough oil or I used the wrong type. I checked the oil, 10w/40 and I put in about 1.3 quarts in. Then I laughed at myself, fuel switch was not flipped to run. Flipped it on and it runs like a dream. The oil that came out was thick black and I can't believe it was that dirty in 190km from city riding. I will take it out another day as I'm about to watch a movie with the Mrs, to do some real testing. But so far, it seems the problem has resided.

[BlackBike]

How bad? Get that oil and put in suspension, then pour a small amount on a white paper plates and take a pic. Some of these guru can tell if it's something serious going on inside. If your worried about you may want to contact the mothership (csc). Small amounts are normal. Here's my first from the bashan as to compare.
6823

[2LZ]

UPDATE*** I took off the sprocket cover to see if I could see anything wobble and I shifted through some gears and it seems to have disappeared which leads me to believe it might be a transmission thing. I wonder if I broke some teeth off the sprockets in the gearbox because when accelerating from a stop, it seems like it has to grind and then catch in first gear to get going...

Odds are you may have picked up something on the chain (piece of gravel, etc.) and ran it through the countershaft sprocket, would be my guess.
I'd imagine that busting a tooth off a gear is virtually impossible, especially with the mammoth HP that these put out. ;-)
Also, it's normal for the CG motor countershaft sprocket to wiggle. That's why I'm not concerned about running a flat sprocket on the rear and having the length of the chain make up the 4mm +/- offset.....or "we'll see".

Keep us posted.

[PNWDualRider]

How bad? Get that oil and put in suspension, then pour a small amount on a white paper plates and take a pic. Some of these guru can tell if it's something serious going on inside. If your worried about you may want to contact the mothership (csc). Small amounts are normal. Here's my first from the bashan as to compare.
6823

The shavings inside my oil for like small pieces of glitter. I thought I'd tear off the sprocket cover and investigate the teeth and all looked well. I decided to tighten the 2 bolts that hold on the front sprocket to see if maybe he knocking was a loose bolt on the front sprocket and the first, perfectly tightened, the second moved freely and so I loosened softly and the bolt fell out completely stripped! I can not believe this was so stripped from the factory. It has been held on by one bolt this whole time... That could've been really bad... But I will purchase a new bolt from the hardware store possibly Thursday before my trip to see if that was the issue.

On a side note, look what else came today! ;)

[PNWDualRider]

The shavings inside my oil for like small pieces of glitter. I thought I'd tear off the sprocket cover and investigate the teeth and all looked well. I decided to tighten the 2 bolts that hold on the front sprocket to see if maybe he knocking was a loose bolt on the front sprocket and the first, perfectly tightened, the second moved freely and so I loosened softly and the bolt fell out completely stripped! I can not believe this was so stripped from the factory. It has been held on by one bolt this whole time... That could've been really bad... But I will purchase a new bolt from the hardware store possibly Thursday before my trip to see if that was the issue.

On a side note, look what else came today! ;)

Picture attached of the bolt holding on my front sprocket.

[Bruce's]

Purchasing a new bolt might not help much ,those buggered up threads have more than likely transferred to whatever they were threaded into .I guess it's pretty safe to say you did not remove ,locktite ,then tighten every fastener you could find while assembling your bike ?

[PNWDualRider]

Purchasing a new bolt might not help much ,those buggered up threads have more than likely transferred to whatever they were threaded into .I guess it's pretty safe to say you did not remove ,locktite ,then tighten every fastener you could find while assembling your bike ?

CSC assembled the bikes for us and they mentioned they used loctight on all the bolts. Hopefully I can replace the bolt, if not, a warranty repair will be in order as I have been obeying all of the warranty regs without a fail for the break in period. I tightened almost all the other bolts except these two... My mistake...

[BlackBike]

CSC assembled the bikes for us and they mentioned they used loctight on all the bolts. Hopefully I can replace the bolt, if not, a warranty repair will be in order as I have been obeying all of the warranty regs without a fail for the break in period. I tightened almost all the other bolts except these two... My mistake...

I bet if you I D the part numbers and Emil csc they would ship it to you asap. Cheap part.

[kohburn]

don't forget to run a tap down the hole to clean out thread debris from the stripped bolt.

[ughmas]

I bet if you I D the part numbers and Emil csc they would ship it to you asap. Cheap part.

Gerry shipped me a replacement slider/fastener for my rear caliper that loosened and fell off, no questions asked, and I had it in 3 days. I'm sure they will help you out.

[SeerAtlas]

any idea of what caused the issue? since one was tight and the other buggered up, suspect someone screwed up when they changed the front sprocket?

[kohburn]

cheap low grade bolt. pretty uncommon for the bolt to strip its own threads instead of what it is going into. granted it was better this way but the bolt should almost always be superior material to what it is going into.

[2LZ]

cheap low grade bolt. pretty uncommon for the bolt to strip its own threads instead of what it is going into. granted it was better this way but the bolt should almost always be superior material to what it is going into.

It was probably run in cross threaded on assembly. So far, all the bolts on the TT have been of a much better quality of ones I've dealt with in the past on older CBs. Odds are this was a fluke.
Go to the hardware store, get a bolt and like kohburn says, run a tap into the hole and clean it out first or you'll have a repeat performance.

[PNWDualRider]

any idea of what caused the issue? since one was tight and the other buggered up, suspect someone screwed up when they changed the front sprocket?

Well, I know that it was buggered up upon assembly or it was a malfunction of some sort. All my worries are gone. Spoke with Gerry and they have assured me all parts are covered under warranty and all will be replaced. This is why I bought from CSC. This company stands behind their products and I couldn't be happier with their service.

[PNWDualRider]

I'm just hoping it didn't strip out the hole that it went into. Which case, more parts needed and more work to be done. However I bought my bike for my family reunion in the mountains this Thursday through Sunday and I'm going to be very disappointed if it's not up and running by then. :/

[wilserchinarider]

I'm just hoping it didn't strip out the hole that it went into. Which case, more parts needed and more work to be done. However I bought my bike for my family reunion in the mountains this Thursday through Sunday and I'm going to be very disappointed if it's not up and running by then. :/

From the looks of the bolt, I would request a yhe bolts and a replacement sprocket as well from CSC. Sure you could run a tap through it as suggested if you have one, but the "warranty" should replace parts required, not require you to repair parts damaged during assembly.

edit...the sprocket is likely much harder steel than the bolt and may not be damaged, you could try and source a bolt locally for less than a dollar :) and try and bolt it up? Does the other sprocket bolt thread into the hole?

[PNWDualRider]

From the looks of the bolt, I would request a yhe bolts and a replacement sprocket as well from CSC. Sure you could run a tap through it as suggested if you have one, but the "warranty" should replace parts required, not require you to repair parts damaged during assembly.

edit...the sprocket is likely much harder steel than the bolt and may not be damaged, you could try and source a bolt locally for less than a dollar :) and try and bolt it up? Does the other sprocket bolt thread into the hole?

The holes on the sprocket are what had been stripped out. Messages Ryan, he upgraded me to Gerry and Gerry saw the pictures and the video link and said it was an easy fix and sent the parts out this morning. That is a great release of stress off my shoulders. I'll post back once the parts arrive. In the meantime, I'm installing LED's in the cluster for brighter display and might install the new exhaust while I wait.

[PNWDualRider]

***Update***

I cleaned out the holes in the sprocket and at first glance I thought they were stripped but the grooves were filled with metal shavings. One of them was perfectly fine and the other is 1/4 way stripped. I am waiting for the new sprocket and I'll install. Also purchased some American made bolts. 😀

[sevndaythry]

I had a similar symptom with the weird pattern noise. Mine was from the right side though. Took off the right side cover and there was a shaft with a cup bolted to the end of it. The bolt was loose which allowed that cup to rub the inside of the case. Tightened it up and the noise went away. The problem was intermittent at first and progressively got worse. They aren't kidding when they say Check the torque on ALL the bolts when assembling a china bike.