hi guys , its my first post here  !

im on a bind on my 1981 XV920 chain drive rebuild (wich i think is a TR1 but maybe named differently in Canada)  , one con rod bearing set was worn out and they were green i found the green ones i need online not a problem

rear rod has yellow markings on the bearings , i found the lower one but i cant find the part number of the upper one anywhere .. can only find Green , Brown , Black...

i cant see the punch mark on the crank on the right side and i dont have the pullers to push it out of the left case but considering the rear rod is yellow and has a K5 punched on it  and the front rod K6 and Green i would think it is a 10  because 10 - 6 = 4 wich means green and 10 - 5 = 5 means yellow

all i can see on the crank is the "AM" mark and a "6" or a "9" but the manual says it should be punched on the side not on the edge

(http://smg.photobucket.com/user/peoplecanfly/media/XV920%201981/IMG_20161005_135932_zps8iwgovm6.jpg.html)


(http://smg.photobucket.com/user/peoplecanfly/media/XV920%201981/IMG_20161005_135705_zpsvhe25yxh.jpg.html)


(http://smg.photobucket.com/user/peoplecanfly/media/XV920%201981/IMG_20161004_132651_zpsmbavxsgg.jpg.html)


wondering what to do... tried to substitute the color part of the part number to no success , the missing yellow bearing is the 19 in the list


(http://smg.photobucket.com/user/peoplecanfly/media/XV920%201981/bearings%20selection%20xv920_zpsxmfnvutx.png.html)

i checked various variations and years of the XV with no success , nobody shows any part number for the top yellow for the rear


(http://smg.photobucket.com/user/peoplecanfly/media/XV920%201981/Screenshot_20161003-234442_zpspu1jshbc.png.html)

rear rod , bearings needs a change  i guess , front one were worn out to the copper but i cant feel much with my nail on the crank , i can feel one little roughness at the centerline where the oil hole spins at but the rest seems fine , a little polish would take care of that

front bearings

(http://smg.photobucket.com/user/peoplecanfly/media/14537061_10153953912737045_1578045634_o_zpsedjiqlwl.jpg.html)

do you guys think i need a regrind? cant feel much with my nail

(http://smg.photobucket.com/user/peoplecanfly/media/14536633_10153953912937045_921031969_o_zps74scljlw.jpg.html)

any help would be appreciated , the riding season is almost over .....  :-(

Thanks

The upper half of the bearing for the back cylinder /the one with the notch/ is only available in black/brown/ green, they have the prefix -5G5-, the other half (down) has 4X7. You need 3 of 4X7 and 1 of 5g5.
I would recomment not to use the colors/size Yamaha says you should, by looking at the marks on Rod and crank. In most cases there is too much clearance. Use black or blue for the front and black for the rear, you can measure the clearance with some plastigauge.
Regards Ali

for the rear rod i luckily found a set of barely used yellow ones that im getting tomorrow morning on my way to work , ill be able to plastigage it. and will know what to order if its too loose , if not i got lucky as hell. if too loose ill get the black ones

so for the front one who is maybe more worn out  i would still order green ones but i would get the one step tighter like you suggest so i dont spend the time waiting for another shipment but wich one is it ? blue or black?  in wich order are they getting thighter?  green loose , black tighter , blue more thight?

From tight to loose:
It´s blue, black, brown, green, yellow, but it is about 1/100 mm , so tolerances may occure. Measuring makes you shure

i been able to replace the front K6 rod by a K5 rod with a very good looking used bearing , i plastigauged it , i get a 0.002" oil clearance with a 0.0002" taper on the part of the crank who looks a bit worn out but it may be during the torquing operation that the rod may have moved to the side or something

rear rod is also plastigauged at 0.002"  

should i put it back together ?

well , ill be damned , while cleaning up the crank i noticed i had a big wear step of about .015" on the front rod journal , in the middle in between the counterweigts... :-( ... i mustve done my plastigauge in a nice spot .... crank is trash , found a XV1000 engine getting it tomorrow , will swap the crank , rods , cylinders and the left cover to retrofit the later model xv starting system and fix my starter issue at the same time  annnd oversize it to 1000cc while im there and got the parts :-)