Help & FAQs    Search BCF    Members    Groups    Events Calendar
Resend my activation email : Register : Log in 
BCF: Bike Chat Forums


Why does Yamaha build engines around the starter clutch?

 Reply to topic
Bike Chat Forums Index -> Show & Tell
View previous topic : View next topic  
Author Message

Nobby the Bastard
Harley Gaydar



Joined: 16 Aug 2013
Karma :
PostPosted: 19:09 - 09 Sep 2015    Post subject: Why does Yamaha build engines around the starter clutch? Reply with quote
As I'm sure quite a number of you know, my FZR 1000 exup is a strong bike, but it's plagued with a knackered starter clutch and a desire to keep the middle east rich with it's thirst for 10/40.

So when I returned from the fabled bbq, off it went to my friend's workshop for a strip and rebuild.

So, engine out

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150815_130621_zpsodx5wgvm.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150815_130606_zps1qgqnnxs.jpg

When he removed the carbs, he found out why it tended to stall when hot...

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150815_145505_zpslixz0prk.jpg

Head and pistons off

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150816_145019_zpsvf4bhpkg.jpg

Diirtyyy sump...

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150816_145351_zpsgl28zcxy.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150816_145354_zpsuc2vim9t.jpg

Behind that is...

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150816_145826_zpsazjemwdt.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150816_145829_zpsgumvot7s.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150816_145833_zpsinsvjpiy.jpg

Looking reasonably clean in there...

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150816_145912_zpspxi21nc3.jpg


Let the dog see the rabbit...

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150816_163141_zpsqvvn56jo.jpg

There the little blighter is!

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150816_163144_zpsh0lxk87m.jpg

Shell bearings surprisingly good for a 40k engine

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150817_175416_zps45scvebt.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150817_175422_zpsoaoqnto9.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150817_175425_zps3l21htca.jpg

Head apart...

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150901_182006_zpsoutlgj0u.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150901_191214_zpsuteolifq.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150901_193344_zps5qgggha0.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150901_193351_zpspgdibdfd.jpg

Now, the rebuild....

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150817_175901_zpssa6hhgu0.jpg

New valve stem seals. The old ones were a bit ropey and were no doubt adding to the oil consumption.

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150825_192738_zpsbo6ueodm.jpg

Wrong fucking gasket! Fucking pattern parts... Genuine Yamaha was the best part of £40

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150825_192940_zpsmwh3mucy.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150825_192945_zps8rgzog8h.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150901_182006_zpsoutlgj0u.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150901_200148_zpsefz09ede.jpg

Barrels rough ed up slightly, they were too shiny, apparently. brand new rings added. Further reasons why oil usage was making me a pauper. Crap running in blamed.

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150903_184003_zpslihaubmx.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150903_184022_zpsw63jurby.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150903_184043_zpshnebc2oe.jpg

What the fuck is this shit?

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150905_113530_zpsbkfh0siw.jpg

Engine back in

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150906_133839_zpsichxxtej.jpg

https://i428.photobucket.com/albums/qq9/Nobbythechihuahua/exup%20rebuild/20150906_145723_zpstbhgonb2.jpg

Then it started. And it the engine sounded sweet . .... . apart from the ticking/knocking noise which we couldn't identify a source for and so it was turned off again.

Sump, clutch, oil pump etc was removed so the gearbox could be checked (all fine) and my mechanic was resigining himself to a complete strip and rebuild to find the issue.

Later that evening, it dawned on him that it sounded just like the tick that the clam chain tensioner makes when adjusting. It appears that the ratchet on it isn't working properly when it's positioned for a brand new unstretched cam chain.

Currently awaiting a new sump gasket so we can proceed further and check if the assumption is correct.


The mighty exup will live again!
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050
 Back to top
View user's profile Send private message You must be logged in to rate posts

Suntan Sid
World Chat Champion



Joined: 07 May 2009
Karma :
PostPosted: 11:30 - 10 Sep 2015    Post subject: Reply with quote
Bet you're glad to get that starter clutch sorted.
I'd have been worried every time I went anywhere that it would eventually pack up altogether.
Have you ever had to bump it and, if so, did it start?
Bet you can't wait to hear it howling properly!
____________________
"Everybody needs money, that's why they call it money!" Cool
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts

Nobby the Bastard
Harley Gaydar



Joined: 16 Aug 2013
Karma :
PostPosted: 17:26 - 10 Sep 2015    Post subject: Reply with quote
Suntan Sid wrote:
Bet you're glad to get that starter clutch sorted.
I'd have been worried every time I went anywhere that it would eventually pack up altogether.
Have you ever had to bump it and, if so, did it start?
Bet you can't wait to hear it howling properly!



To be honest, it always started eventually, I've never had to bump it first thing. It was easy enogh to bump when warm.

I'm getting seriously fucked off with getting the train so when I hear it howling, I'll be on it doing the Bristolring...
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050
 Back to top
View user's profile Send private message You must be logged in to rate posts

Acemastr
World Chat Champion



Joined: 01 Oct 2008
Karma :
PostPosted: 20:34 - 10 Sep 2015    Post subject: Reply with quote
Roughed up barrels seems wrong on every level to my mind, but then I'm definitely no expert... thought they needed to be a smooth as possible
____________________
2017 KTM 350 XC-F - 2014 Yamaha R6 - 2005 Yamaha YZ125
2016 Toyota Tacoma Limited
 Back to top
View user's profile Send private message You must be logged in to rate posts

sickpup
Old Timer



Joined: 21 Apr 2004
Karma :
PostPosted: 20:56 - 10 Sep 2015    Post subject: Reply with quote
Acemastr wrote:
Roughed up barrels seems wrong on every level to my mind, but then I'm definitely no expert... thought they needed to be a smooth as possible


Shouldn't be smooth, should be at 45ish degrees. The roughness helps tp retain oil in the bore but horizontal lines will promote excessive piston ring wear.
 Back to top
View user's profile Send private message You must be logged in to rate posts

Ben90
Brolly Dolly



Joined: 06 Feb 2014
Karma :
PostPosted: 21:02 - 10 Sep 2015    Post subject: Reply with quote
Acemastr wrote:
Roughed up barrels seems wrong on every level to my mind, but then I'm definitely no expert... thought they needed to be a smooth as possible


The new rings quickly wear most of it down. The cross-hatch pattern you can see in the cylinder photos is intentional - even down to the angles of the hatch; it creates channels for the oil to work around. The ideal is to get the rings to sit entirely on a film of oil so practically no wear occurs.

Perfectly smooth cylinders wouldn't retain sufficient oil, or so I understand.

Edit: beaten to it Embarassed
____________________
Yamaha FZ6 S2
 Back to top
View user's profile Send private message You must be logged in to rate posts

Nobby the Bastard
Harley Gaydar



Joined: 16 Aug 2013
Karma :
PostPosted: 21:56 - 10 Sep 2015    Post subject: Reply with quote
The photos don't really do the barrels justice.

In reality they've been honed with a 35 degree angle.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050
 Back to top
View user's profile Send private message You must be logged in to rate posts

sickpup
Old Timer



Joined: 21 Apr 2004
Karma :
PostPosted: 07:17 - 11 Sep 2015    Post subject: Reply with quote
Nobby the Bastard wrote:
The photos don't really do the barrels justice.

In reality they've been honed with a 35 degree angle.


How was it done, by hand or honing machine?
 Back to top
View user's profile Send private message You must be logged in to rate posts

MarJay
But it's British!



Joined: 15 Sep 2003
Karma :
PostPosted: 07:43 - 11 Sep 2015    Post subject: Reply with quote
I was always taught that a hone should be done with a rotating honing tool once inwards and once outwards to achieve 45 degree hatching in both directions. Those honing marks look deep and horizontal...

Stan Stephens uses a tool which I think is called a ball hone or something. It looks like this:

https://www.ebay.co.uk/itm/1-5-8-41mm-FlexHone-Flex-Hone-320-grit-Silicone-Carbide-BC15832-/262030320923?_trksid=p2141725.m3641.l6368
____________________
British beauty: Triumph Street Triple R; Loony stroker: KR1S; Track fun: GSXR750 L1; Commuter Missile: GSX-S1000F
Remember kids, bikes aren't like lego. You can't easily take a part from one bike and then fit it to another.
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts

Nobby the Bastard
Harley Gaydar



Joined: 16 Aug 2013
Karma :
PostPosted: 14:46 - 11 Sep 2015    Post subject: Reply with quote
sickpup wrote:

How was it done, by hand or honing machine?


"Use honeing stones on a drill wet using engine oil. Try to get a decent 35 degree cross hone. Hard by hand but pretty close"


Not ideal, I know, but needs must.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050
 Back to top
View user's profile Send private message You must be logged in to rate posts

DJP
Crazy Courier



Joined: 11 Dec 2011
Karma :
PostPosted: 10:26 - 14 Sep 2015    Post subject: Reply with quote
Nobby the Bastard wrote:
The photos don't really do the barrels justice.

In reality they've been honed with a 35 degree angle.


They look fine to me.
____________________
Suzuki Bandit 1250
https://deejayp999.atwebpages.com/index.html
That's http not https
 Back to top
View user's profile Send private message You must be logged in to rate posts

bladeblaster
Trackday Trickster



Joined: 19 Jan 2015
Karma :
PostPosted: 15:57 - 14 Sep 2015    Post subject: Reply with quote
Its not just Yamaha, Kawasaki also bury it deep in the bowels of the gearbox.

Or at least they did on the GPz900
 Back to top
View user's profile Send private message You must be logged in to rate posts
Old Thread Alert!

The last post was made 9 years, 280 days ago. Instead of replying here, would creating a new thread be more useful?
  Display posts from previous:   
This page may contain affiliate links, which means we may earn a small commission if a visitor clicks through and makes a purchase. By clicking on an affiliate link, you accept that third-party cookies will be set.

Post new topic   Reply to topic    Bike Chat Forums Index -> Show & Tell All times are GMT
Page 1 of 1

 
 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 vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum

Read the Terms of Use! - Powered by phpBB © phpBB Group
 
Debug Mode: ON - Server: birks (www) - Page Generation Time: 0.06 Sec - Server Load: 0.49 - MySQL Queries: 13 - Page Size: 83.83 Kb