Topic: CB750: Aware of cheap parts -tensioner rubber cracked in 2- Carb boots cracking

[CycleRanger]

The OEM tensioner roller is probably made of extruded compression-formed vulcanized rubber. (Like a hockey puck)
Whereas the aftermarket rollers are probably just just some kind of molded thermoplastic.

[theslayedsaint]

Did anyone get hurt or case extra motor damage from the roller breaking?

[Retro Rocket]

Did anyone get hurt or case extra motor damage from the roller breaking?

Have a look at the first pic in post one of this thread, Pewe was only moments from disaster...

[theslayedsaint]

So dare I ask where everyone bought there replacement from? I know I'm getting Honda but just off eBay?

[beemerbum]

Davis Silver Spares has Honda cam chain tensioner parts

[HondaMan]

I've bought ones from Honda that only have the Honda labels, and I have bought them from other vendors (PartsNmore, CB750Supply (long ago), VintageCB750, 4into1.com) that were mostly labelled "Made in Taiwan", but at least one of these others was labelled "Made in Japan". I know this just adds to the confusion, though. The non-Honda versions (Japan and Taiwan) all came as "kits" with the tensioner roller, tensioner arm, slider tensioner, and the bearing. The Honda stuff is part-by-part.

[AshimotoK0]

On the large cam chain tensioner  roller common to the  CB350K & CB750 SOHC motors  does anyone know what the David Silver repro ones are like? I have a couple BNIB.

He won't tell me who makes them or the rubber spec. I am inclined to just cut my loses and order the Genuine ones from Honda. He tells me he has sold a large quantity and never had any complaints.

Everyone on the UK tells me Cruzinimage pistons & rings are fine but reading on other forums that there rubber parts are not brilliant, I am inclined to fit either Riken or NRP rings ?

[PeWe]

Tensioner kit update: I got my money back without asking for it! PayPal refund end of last week.
I was sure that the warranty period was over since I bought the tensioner kit 2012, installed it 2013, on the road 2014.

VintageCB750 do what they can.    Really Good!!!

I guess they will prioritize quaility products in the future which will gain all their customers.

[grcamna2]

PeWe,
Have you installed the steel rollers into your engine and running around with them and putting km.'s on your bike ?

[SunLar]

Tensioner kit update: I got my money back without asking for it! PayPal refund end of last week.
I was sure that the warranty period was over since I bought the tensioner kit 2012, installed it 2013, on the road 2014.

VintageCB750 do what they can.    Really Good!!!

I guess they will prioritize quaility products in the future which will gain all their customers.

Bought this from CMSNL and just installed it 3 days ago. Bloody hope it´s ok.

[PeWe]

PeWe,
Have you installed the steel rollers into your engine and running around with them and putting km.'s on your bike ?

Engine is still open. I have not pressed the upper steel roller together yet. I have only one chance to get it right.
I have also a new Honda tensioner to use.
Waiting for Cyl + pistons and for head job. Front end restore/upgrade while waiting
I hope end of this month.

[theslayedsaint]

Just a side note! VintageCB750 also stopped selling the upper pucks so again something that i could use the gift card for to rebuild the top end they "stopped" selling good timing on there part. lol

[katman]

This Really sucks. I just got notified over the weekend. Put a set from them in my 77 750K when I redid the whole bike.
I ride my 75 more. 77 only has 325 miles since topend. Now I have to pull the engine back out! F?/*%#!!

[grcamna2]

PeWe,
Have you installed the steel rollers into your engine and running around with them and putting km.'s on your bike ?

Engine is still open. I have not pressed the upper steel roller together yet. I have only one chance to get it right.
I have also a new Honda tensioner to use.
Waiting for Cyl + pistons and for head job. Front end restore/upgrade while waiting
I hope end of this month.

With the steel quality rollers(w/ the teeth) you may only hear more 'whirring' sounds coming from the engine,that's not bad.

[HondaMan]

Tensioner kit update: I got my money back without asking for it! PayPal refund end of last week.
I was sure that the warranty period was over since I bought the tensioner kit 2012, installed it 2013, on the road 2014.

VintageCB750 do what they can.    Really Good!!!

I guess they will prioritize quaility products in the future which will gain all their customers.

Bought this from CMSNL and just installed it 3 days ago. Bloody hope it´s ok.

Out of curiosity: was/is this one marked "Made in Japan", or "Made in Taiwan"?

[madmtnmotors]

Bought this from CMSNL and just installed it 3 days ago. Bloody hope it´s ok.

For 6.50 euros I would say they are highly suspect. If you decide to "let it ride" I would highly recommend a borescope and that you monitor its condition periodically by removing the tensioner arm and checking it out every 500 miles. Pewe's tensioner wheels self destructed at less than 3000 miles. Mine were on the verge of shedding chunks at 1700 miles... 

Of course, for the price of a cheap borescope you could probably buy original Honda parts... 

[PeWe]

Tensioner kit update: I got my money back without asking for it! PayPal refund end of last week.
I was sure that the warranty period was over since I bought the tensioner kit 2012, installed it 2013, on the road 2014.

VintageCB750 do what they can.    Really Good!!!

I guess they will prioritize quaility products in the future which will gain all their customers.

Bought this from CMSNL and just installed it 3 days ago. Bloody hope it´s ok.

That lower bigger wheel did not fall into pieces in my engine, it was the upper small wheel pressed together with the steel plate thing
 14500-300-000. Included in the complete kit made in Taiwan
This seems to be HONDA original part
http://www.cmsnl.com/honda-cb750k6-four-european-direct-sales_model14384/tensioner-chain_14500300000/#.VwOK3PmLTcs
The upper smaller wheel is the one of the 2 cam chain tensioner wheels that get most wear, right?

[katman]

So were should I purchase a new upper roller assembly and know I am getting a decent one

[madmtnmotors]

So were should I purchase a new upper roller assembly and know I am getting a decent one

Honda

[grcamna2]

The steel roller kit that PeWe posted earlier in this thread would be my choice,there is no rubber to degrade.

[theslayedsaint]

I'm going OME made in Japan! Some of these bikes are still on the rode with no engine work done since the 70s.

[Harsh]

So I have been away from the forum for a while.  Silly Navy making me go places.  Ha...but I got them...I retire in 17 days.

I received three emails today from VintageCB750.  The first was a refund of $87.95 to my paypal account.  The second was a $50 gift certificate.  At this point I was thinking a scam of some sort trying to get me to click the links in the emails and login to my account so they could get my password and fleece my account.  Then I received the third one titled Important Safety Notice.  Within the email they stated that their records showed that on April 30, 2012 I purchased a cam chain tensioner set and that they have had issues with the parts supplied.

I wasn't planning on tearing down my engine, but I guess I will be now.  I guess it is a good time to get one 754's weldless frame kits.

[PeWe]

So were should I purchase a new upper roller assembly and know I am getting a decent one

I bought from David Silver and got Honda labeled bags Made in Japan
https://www.davidsilverspares.co.uk/parts/by-part-number/partnumber_14500300000/
Then the other bigger lower wheel
https://www.davidsilverspares.co.uk/parts/by-part-number/partnumber_14601312000/

CMSNL has these too
http://www.cmsnl.com/honda-cb750k6-four-european-direct-sales_model14384/tensioner-chain_14500300000/#.VwOK3PmLTcs
http://www.cmsnl.com/honda-cb750k6-four-european-direct-sales_model14384/roller-camchain_14601312000/#.VwP4XKSLTIU

[grcamna2]

So I have been away from the forum for a while.  Silly Navy making me go places.  Ha...but I got them...I retire in 17 days.

I received three emails today from VintageCB750.  The first was a refund of $87.95 to my paypal account.  The second was a $50 gift certificate.  At this point I was thinking a scam of some sort trying to get me to click the links in the emails and login to my account so they could get my password and fleece my account.  Then I received the third one titled Important Safety Notice.  Within the email they stated that their records showed that on April 30, 2012 I purchased a cam chain tensioner set and that they have had issues with the parts supplied.

I wasn't planning on tearing down my engine, but I guess I will be now.  I guess it is a good time to get one 754's weldless frame kits.

Good to hear you Harsh,
I'm happy for you retiring in 17 Days !

[Harsh]

So I have been away from the forum for a while.  Silly Navy making me go places.  Ha...but I got them...I retire in 17 days.

I received three emails today from VintageCB750.  The first was a refund of $87.95 to my paypal account.  The second was a $50 gift certificate.  At this point I was thinking a scam of some sort trying to get me to click the links in the emails and login to my account so they could get my password and fleece my account.  Then I received the third one titled Important Safety Notice.  Within the email they stated that their records showed that on April 30, 2012 I purchased a cam chain tensioner set and that they have had issues with the parts supplied.

I wasn't planning on tearing down my engine, but I guess I will be now.  I guess it is a good time to get one 754's weldless frame kits.

Good to hear you Harsh,
I'm happy for you retiring in 17 Days !

Thanks.  Hopefully my job hunt starts getting better.  Military retirement won't pay the bills.

This is looking to be an expensive repair.  I have one of the few made engines that used some o-rings (HSB # 42 p/n 12115-300-305) vice the knock pin seals.  Last I knew Western Hills Honda had one set left, but that was 4 years ago.  Regardless, new gaskets, replacement parts (leaning towards the metal gears), and frame kit.  I am likely to be in this for a few hundred bucks.  Not to mention the time I don't really have to do the work.