need a new "D" camshaft bearing cap - where to buy?

[4twizzle]

Anyone know where I can find a replacement bearing cap for valve "D"?  I checked bikebandit and a few other places already and came up with nothing.  They don't even get their own number on the diagram.   

[gregvhen]

cant buy them, you need a whole new head with them on it. they have to go with the same head they are made for......sorta

[gregvhen]

i broke two a while back, and i had got some from a member on here who was parting out. everyone will tell you that you CANT swap caps, or get new ones, but when the ones i was sent came in the mail i used a caliper to measure the circle that the cam rides in, in 6 spots and they all showed it to be a true circle. but i got extremely lucky, one cap fit perfect in one spot, and the other cap fit in the other and i never had problems with them since. but, its a chance.  you should try to buy a full head off of a part out.  and if you do just find caps somewhere, make sure you measure with a caliper, not just a ruler. its important stuff

[4twizzle]

I just noticed the for sale section of the forum, and threw a post up in there.

Thanks for the help!

[sledge]

Its not just a question of if they will fit, you have to consider tolerances. Its a question of if they will fit and at the same time maintain concentricity between the cap and head, the oil clearance between the cap and camshaft and alignment with the bearing on the other side of the camshaft.

Consider it this way.......
If you use a mix and match cap that has been bored out to a figure that is at the upper limit of tolerance with a head thats been bored to a figure at the lower limit of tolerance you will have a journal that is not concentric, put simply the upper half will be a bigger diameter than the lower half and there will be a step at each side of the joint.

Suzuki quote an oil clearance figure of 0.03-0.06mm with a service limit of 0.15mm between the camshaft and cap and that assumes the cap and head line up perfectly to form an exact circle without leaving a step on each side of the joint line and that it is in exact alignment with the bearing on the other side of the camshaft. The only way to check for concentricity is by taking and comparing readings with a 3-point internal micrometer and by using plastiguage for the clearance.

Caps are not available seperately because Suzuki dont manufacture them seperately and to a tolerance that will allow 100% interchangeabilty, probably because its not cost effective.

You might get lucky swapping and changing caps and land in the ballpark but you will never get them as close as the factory does owing to the fact they made as an integral part of the head and if you are outside of the figures Suzuki quote you are on your own