Gauloises YZR500 3MA (Mistress)

Message

Dubsey · #31 Post by **Dubsey** » Mon Jan 26, 2009 9:55 pm

Jordi YZR500 and rzatch after much head scratching, I may have found a possible solution to the rear of the tail unit !
I am making a mould of the existng rear section, I will then make a copy, and use this to model a new seat hump, similar to wolfgangs and earlier yzr's

rzatch · #32 Post by **rzatch** » Tue Jan 27, 2009 12:18 am

Dubsey an easy way to protect the original is to use plastic wrap that is designed for food. Just stretch it tight on the original and lay the glass over it. May need to use a little tape here and there to hold it.

Dubsey · #33 Post by **Dubsey** » Wed Jan 28, 2009 5:37 pm

After making the mould for the hump,
I decided the only option was to cut the seat in half,
and alter the top pipes !
I also added another strip to the bottom edge

rzatch · #34 Post by **rzatch** » Wed Jan 28, 2009 8:20 pm

Just when you thought you had it figured out you showed us pictures. Brave soul doing that again! But we all like pictures

That looks good, much better.

rusell · #35 Post by **rusell** » Thu Jan 29, 2009 11:41 am

much better

Dubsey · #36 Post by **Dubsey** » Wed Feb 04, 2009 4:56 pm

fairing by Wolfgang

Andrew · #37 Post by **Andrew** » Thu Feb 05, 2009 9:45 am

Looking 100% better.

geosot · #38 Post by **geosot** » Thu Feb 12, 2009 7:37 am

It looks like the engine is positioned way to front or way to close to the forks.

I know that NK insists on position the engine not tilted front or closer to the OEM ancle;

But it seems to be a considerable distance between the counter shaft sprocket and the swing arm pivot.

In order to position the engine closer to the swingarm pivot you have eiither

1. to tilt the engine front, or

2. to remove a part of the top frame crossmember, about 15 mm x 30 mm and to modify the clutch cover. BUT top frame cross member holds the top shock mount, so further reinforcing of the area is needed. More welding, more heat more metal distortion.

At the end position the engine as it is, it is not that bad.

George

Dubsey · #39 Post by **Dubsey** » Thu Feb 12, 2009 5:22 pm

I agree, the engine does appear to be very close to the front wheel.
The engine mounts were done by Nigel Kimber, so I must consider these to be in the correct position.
I have tie strapped the front end down, and bottomed the forks out, the front wheel just kisses the plug caps, if the wheel is turned/steered, so I figure that it should be ok
When riding, if I were to bottom the forks whilst turning, I would end up in a ditch lol
I am using R1 forks and heavily modified R1 yokes.
The R1 yokes have very little offset, and no step down.
If it does turn out to be an issue, I do have another set of yokes, that have more offset and stepdown, but these and the wheel will need machining to fit.
On another note the weight distribution should be interesting if the engine is too far forward.
What is the best weight distribution ?

geosot · #40 Post by **geosot** » Thu Feb 12, 2009 5:50 pm

The weight distribution should be OK, since the R6 swingarm is longer than the 3MA arm (about 1 and 1/2 ").

Nigel insists in placing the engine not tilted front and I agree with him. I don't think that tilted engines work properly in the long run (despite the oil pump)

Sprocket, swingarm pivot and rear wheel axle are aligned properly.

G

Dubsey · #41 Post by **Dubsey** » Thu Feb 12, 2009 6:08 pm

The sprocket hub has been machined to the maximum,
and the offset was still not right,
if i had offset the front sprocket to accomadate this,
the chain hits the frame,
so I have made a sprocket carrier,
and have had a sprocket (520) made to fit this,
this carrier brings the sprocket in board of the sprocket hub face,
its the same idea as an offset sprocket but alot cheaper.

#42 Post by **smurph** » Thu Feb 12, 2009 7:55 pm

If you go with another yoke, don't go more than 35mm offset! It will slow things down. What year yokes are you using now?

98-01 35mm offset
02-03 25mm offset
04-05 30mm offset

Steve

Dubsey · #43 Post by **Dubsey** » Thu Feb 12, 2009 8:18 pm

I'm using 2006 R1 5VY
do you know the offset for these ?
the other set I have is TZR 3ma but those are 10mm narrower and the bottom yoke will need opening up
or I have the option of having a set made at Ã‚Â£500
unless anyone knows of other yokes that would suitable ?
or possibly a stepped top yoke ?

rzatch · #44 Post by **rzatch** » Thu Feb 12, 2009 9:42 pm

Dubsey have a look at this post. Your already dealing with the guy that makes them!

http://www.rzrd500.com/500phpBB3/viewto ... gel+kimber

Scroll down to the BikePics link in Chris's post.

Dubsey · #45 Post by **Dubsey** » Thu Feb 12, 2009 10:37 pm

I have met nigel and been to his workshop,
The stepped top yoke (apart from cost) is definately the way to go, but I do have one more cheaper idea, but will use that if it becomes necessary !
For the moment I will leave as is and see if it becomes an issue, but as I said the wheel only just touches the plug caps on full compression, suspension bottomed out with the use of 5 ton tie strap

I suppose after all this if it doesn't work it'll be a lovely ornament