RZ/RD 350 & Misc. 2-Stroke Tech BBS

Technical Forums for Two-Stroke Nuts
It is currently Wed Aug 15, 2018 4:02 am

All times are UTC - 4 hours [ DST ]




Post new topic Reply to topic  [ 30 posts ]  Go to page Previous  1, 2
Author Message
 Post subject:
PostPosted: Mon Dec 03, 2007 12:29 pm 
Offline

Joined: Wed Oct 05, 2005 6:09 pm
Posts: 157
They have both, clutch and rear wheel cush drive. Michael


Top
 Profile  
Reply with quote  
PostPosted: Thu Jan 18, 2018 2:33 pm 
Offline

Joined: Mon Jul 03, 2017 7:01 am
Posts: 61
Location: Norway
Hi
Can anyone shed any light on how to make sure the cranks stay 180 after a center bearing/seal rebuild?
I do have access to a hydraulic press and figure the outer webs and big ends should be achieveable, but center "180 degree truing" of the crank pins seems challenging since it cannot easily be measured by a runout guage?

Regards
kjell

_________________
----------------------------------
RD350 YPVS 1990
N2 Red/white - F2 conversion
Figaroli pipes


Top
 Profile  
Reply with quote  
PostPosted: Thu Jan 18, 2018 5:43 pm 
Offline

Joined: Fri Feb 17, 2012 10:54 pm
Posts: 78
Location: Omemee, Canada
The two center pieces are splined, so not adjustable.


Top
 Profile  
Reply with quote  
PostPosted: Thu Jan 18, 2018 6:36 pm 
Offline

Joined: Mon Jul 03, 2017 7:01 am
Posts: 61
Location: Norway
I am a little confused about that;
But, I probably should have stated that I was asking for a 1990 F2 specifically in case this matters.
- And in another thread I was pointed to Yambits for pictures of the centre webs;
https://yambits.co.uk/crankshaft-parts- ... pqck2nop12

I cannot see that any of the 350 centres has splines ?
And if they dont my question remains.

_________________
----------------------------------
RD350 YPVS 1990
N2 Red/white - F2 conversion
Figaroli pipes


Top
 Profile  
Reply with quote  
PostPosted: Thu Jan 18, 2018 7:05 pm 
Offline
Moderator
User avatar

Joined: Sat May 07, 2005 12:02 am
Posts: 1751
Location: Cullman, AL
When assembling a crank from new parts, a fixture (sometimes referred to as a "jig") is used to properly align the crank web for 180 degree offset pins on the center section. If you are rebuilding one, you might be able to get away without using a fixture, assuming you are reusing the crank webs that went with the center bearing. Just mark which web goes to which end of the center bearing shaft and be careful. Measure 8 times, press once. :) Otherwise, you will need to make a fixture.

Typically, the center section is not rebuilt, but replaced, as a lot more tools are needed to rebuild them. It is WAY more economical to buy the center section because you will invest more time and money making a fixture than what the center section costs. Make a fixture if you foresee rebuilding many cranks in the future.

Steve

_________________
Fuel Injected RZ350


Top
 Profile  
Reply with quote  
PostPosted: Thu Jan 18, 2018 7:46 pm 
Offline

Joined: Mon Mar 03, 2014 8:44 pm
Posts: 2812
Location: Alberta, Canada
As above, unless you have all the tooling and knowledge to do the work, just buy a new crank and then have that trued.

_________________
Rory


Top
 Profile  
Reply with quote  
PostPosted: Fri Jan 19, 2018 11:46 am 
Offline
-----
-----
User avatar

Joined: Sun Nov 23, 2008 2:22 pm
Posts: 1645
Location: Livermore, CA
Welcome back! :smt045 I hope all is well and we see more posts from you. :smt023

smurph wrote:
When assembling a crank from new parts, a fixture (sometimes referred to as a "jig") is used to properly align the crank web for 180 degree offset pins on the center section. If you are rebuilding one, you might be able to get away without using a fixture, assuming you are reusing the crank webs that went with the center bearing. Just mark which web goes to which end of the center bearing shaft and be careful. Measure 8 times, press once. :) Otherwise, you will need to make a fixture.

Typically, the center section is not rebuilt, but replaced, as a lot more tools are needed to rebuild them. It is WAY more economical to buy the center section because you will invest more time and money making a fixture than what the center section costs. Make a fixture if you foresee rebuilding many cranks in the future.

Steve

_________________
1983 rwb RZ350 Canadian stock (exc toomeys)
1985 rwb RZ350NC vm30,pods,porting,spec2 pipes
1985 yb RZ350 rat driver,fz/fzr parts,fox shock,vm30,pods,porting,toomeys
1985 RZ350 black? fz/fzr susp (in process)
more RZ350s on hold
1985 RZ500 (done, yah sure)


Top
 Profile  
Reply with quote  
PostPosted: Fri Jan 19, 2018 1:12 pm 
Offline

Joined: Tue Nov 12, 2013 2:34 am
Posts: 1087
Cranks are all the same be it 83 or 90 RZ or a banshee during their long run. Thankfully due to the banshee we have super cheap cranks available new.

Doesn't really make sense to rebuild. 11 years ago when this thread was started the cost of a rebuild was still almost as much as the cost of a new crank today....

Crank and barrel work are the only 2 items I farm out to other trades. Have seen crank jigs for sale before which were expensive and made of quite thick steel.


Top
 Profile  
Reply with quote  
PostPosted: Sat Jan 20, 2018 5:01 am 
Offline

Joined: Mon Jul 03, 2017 7:01 am
Posts: 61
Location: Norway
I agree with the pricing of new cranks. They are not to bad . But for the hard dyi guys, i found this on how to rebuild even the centers, by using a jig. But I believe it can be done without as well. The key is to check the 180 accuracy afterwards and this links shows how this can done. Even useful just for checking a good crank.
https://www.bansheehq.com/forums/index. ... lkthrough/

_________________
----------------------------------
RD350 YPVS 1990
N2 Red/white - F2 conversion
Figaroli pipes


Top
 Profile  
Reply with quote  
PostPosted: Sat Jan 20, 2018 9:25 am 
Offline
User avatar

Joined: Fri Nov 01, 2013 8:34 pm
Posts: 1322
Location: back in the hills
A Yamaha 'Shee crank is $404 and shipping. Why not?

_________________
There is only one difference between a madman and me. The madman thinks he is sane. I know I am mad.
Salvador Dali


Top
 Profile  
Reply with quote  
PostPosted: Sat Jan 20, 2018 8:22 pm 
Offline
Moderator
User avatar

Joined: Sat May 07, 2005 12:02 am
Posts: 1751
Location: Cullman, AL
kjellz wrote:
I agree with the pricing of new cranks. They are not to bad . But for the hard dyi guys, i found this on how to rebuild even the centers, by using a jig. But I believe it can be done without as well. The key is to check the 180 accuracy afterwards and this links shows how this can done. Even useful just for checking a good crank.
https://www.bansheehq.com/forums/index. ... lkthrough/


Yeah, well... don't go measuring unless you want to find how bad out of spec the production stuff is! It can be downright depressing. But for the most part, it still works fine. Sometimes ignorance is bliss. :)

Steve

_________________
Fuel Injected RZ350


Top
 Profile  
Reply with quote  
PostPosted: Sun Jan 21, 2018 12:36 am 
Offline
User avatar

Joined: Thu Aug 05, 2010 2:21 am
Posts: 125
Location: Alberta Canada
It was a lot easier with the early RD & TZ cranks as they had large splines & the centre cheeks lined up pretty good. The downside was one would occasionally crack, which is why Yamaha went to the micro-splined centre pin. I hate that the crank pin is now part of the flywheel though...

_________________
"...its a 2-stroke ya twit - Its supposed to smoke..."


Top
 Profile  
Reply with quote  
PostPosted: Sun Jan 21, 2018 11:58 am 
Offline
User avatar

Joined: Fri Nov 01, 2013 8:34 pm
Posts: 1322
Location: back in the hills
I never install a crankshaft w/o measuring and truing. Even if was true from the factory who knows what UPS?USPS/FedEx put it through. Not to mention the trip from the east.

_________________
There is only one difference between a madman and me. The madman thinks he is sane. I know I am mad.
Salvador Dali


Top
 Profile  
Reply with quote  
PostPosted: Mon Jan 22, 2018 2:46 am 
Offline

Joined: Mon Mar 03, 2014 8:44 pm
Posts: 2812
Location: Alberta, Canada
Agreed. They have to be checked before you plunk them in!

_________________
Rory


Top
 Profile  
Reply with quote  
PostPosted: Wed Jan 24, 2018 1:16 pm 
Offline

Joined: Tue Nov 12, 2013 2:34 am
Posts: 1087
Also make sure all go through my engine building. Key to a smooth revving engine.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 30 posts ]  Go to page Previous  1, 2

All times are UTC - 4 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 6 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group