Rd350 A/B crank pin 8G8-11681-00

[Pravin]

Hi ,

I have to rebuild my crank due to issues as it seems the weight is lose or my webs are rubbing in cenak case giving silver flakes ..very fine ones and powder like lead deposition on to head and piston top area ..even my right plug is silver grey ...

I have been looking and found the part number 8G8-11681-00 but this one looks to be solid pin and the ones came in bikes in India were hollow ones .

Do we have any part number to look for hollow crank pins ? and can I use these solid ones in case I don't get hollow ones ? Any impact ?

Regards,
Pravin

[m in sc]

wait. didnt the crank just get 'trued' on this?

Id look to get a vitos crank if you can. or just buy 2 matching pins and replace them both.

[bitzz]

Yamaha stopped using the hollow pin
AFIK all the Yamaha crank pins supercede to the RD400 solid pin with serrated edges.
Wiseco makes a hollow pin or use  Kawasaki  13035-1010-01

If you're going to replace the pin, you're going to replace the rod and big end bearing... NO?
Get a ProX kit with pin, rod, bearing and thrust washers, everything you need, all in one box.

[Pravin]

wait. didnt the crank just get 'trued' on this?

Id look to get a vitos crank if you can. or just buy 2 matching pins and replace them both.

Yes crank was trued to zero and I installed it ... I doubt it's the crank web rubbing or lead weights rubbing somewhere ...

Am looking for pins but all are solid pins not hollow .... Wil ot be okay ?

Regards,
Pravin

[Pravin]

Yamaha stopped using the hollow pin
AFIK all the Yamaha crank pins supercede to the RD400 solid pin with serrated edges.
Wiseco makes a hollow pin or use  Kawasaki  13035-1010-01

If you're going to replace the pin, you're going to replace the rod and big end bearing... NO?
Get a ProX kit with pin, rod, bearing and thrust washers, everything you need, all in one box.

I guess the prox is best bet .... I do have 360 rods n small ends ....was planning to buy big ends n pins off ebay but the pins are like 30$ each ..

Regards,
Pravin

[Pravin]

Pics ...how it looks ..

Missed flakes on the cloth I thin it got deleted

[Pravin]

 More pics

[1976RD400C]

Did you take a close look at your crank? Are the flywheels spreading apart and rubbing on the case? What is the clearance on the rod large end where the thrust washers are? Any pics of the piston skirts and cylinder bores?

[m in sc]

you need to take the crank out and inspect it. id still just replace it. especially if this is going to be stock pipes, it wont get stressed that much.

[Pravin]

Did you take a close look at your crank? Are the flywheels spreading apart and rubbing on the case? What is the clearance on the rod large end where the thrust washers are? Any pics of the piston skirts and cylinder bores?

There is 2to3 mm side play in rods no verticle .. I tried to check the webs and weight is they move side ways with a flat  screw driver but they don't look snug fit .

I had out back the too end with new piston pin bearings ...cleaned the head n piston ..right one and am going to ride for 10 20 km and see if I still get that grey deposition on plug n heads n piston top ...if so am going to split open the engine .

If not then the rubbing has done whatever it could and that's it !!

I still have bearings sound which I need to address once I gather all parts and that time am gona open the engine as well anyways..

Don't want to spend double on engine work labor .

Cheers
Pravin

[m in sc]

if you can move the weights, stop riding it. 

[pidjones]

if you can move the weights, stop riding it.

Agreed. And, the bearing sound is probably the grey matter getting into the races. Keep running it, and the cost of repair can go up by 3X to 5X.

[rodneya]

if you can move the weights, stop riding it.

Agreed. And, the bearing sound is probably the grey matter getting into the races. Keep running it, and the cost of repair can go up by 3X to 5X.

Or all the dirt that is in the engine. The area around the crank bearing oil holes does not look good at all and who knows what has made it into the bottom of the motor.

[m in sc]

true. ive seen a bearing lock up and completely fuck up a set of cases by spinning in the case. 

[Pravin]

Hmmm ok I think I need to open the engine up !!

Will keep you guys posted !

Regards,
Pravin