Amount and thickness of fork oil for a '81 Kat 1100???

[robinjo]

The guy I bought the Katana from was going to get me workshop manual since he works for a bike dealer and get it at a discount but he appears to fallen of the face of the earth...

I don't think that the data for a '81 GS1100 will work for a Kat based on the fact that in a period roadtest it was mensioned that the Katana had much harder suspension then the "normal" 1100. The suspension was softened in '82 or '83 to a more normal setting but I have the '81 model.

Read in a scanned online Katana owners manual that the amount of oil was 277ml but don't know if this applies for my model and it didn't give a viscosity.

Right now the front forks are much softer than the new original rear shocks set at lowest preload and damping (5-way preload and 4-way dampning) and the bike weaves in fast corners, it handles worse than my GS1000S wich was pretty stable up to the point of scraping the centerstand but I set it up pretty precise. The bike has new tires (BT45 Battleax's) at the correct pressures and no play in the swingarm bearings or steeringhead.

 

[Hap Call]

Here in the USA we had the 1000Kat in '81. I have the factory service supplement...when I get home I will see what it says about the amount of oil. The weight depends more on your preferences...I will try to find the factory weight also so you can have a starting point.

Hap

 

[robinjo]

Here in the USA we had the 1000Kat in '81. I have the factory service supplement...when I get home I will see what it says about the amount of oil. The weight depends more on your preferences...I will try to find the factory weight also so you can have a starting point.

Hap

Thanks in advance Hap, I personally think it's important to find a good balance between front and rear suspension so this wil help . Get the right damping on the front and adjust the rear shocks accordingly. Nothing to adjust at the front and God knows how old the oil is that is in there now :roll:.

 

[saaz]

Sounds like a suspension imbalance..the Kats were a bit firmer. I assume wheel alignment is ok? If you had the GS set up properly, obviously you know whats what!

I did find the BT45s a bit more wandery than other tyres (on a GS1000), but no more so than the old Pirelli Phantoms.

 

[robinjo]

I'm actually not a big fan of the BT45's but they were on when I bought it a few weeks ago and they need a lot of heat to work properly. Macadam's worked well on the 1000S and KGB recommended Dunlops GT501.

Checked out the sag of the front suspension yesterday and with driver it was 61mm, recommended is 25 to 30% of the total travel wich is 150mm so while I'm working on the front I'm gong to put in some 11mm spacers on top of the springs. The front forks have 4-way pre-load but it is stuck at the moment, gonna check that out also.

 

[robinjo]

Hap?...Katana owners?...anyone?

I wanna get rid of this little edge 8O

 

[Hap Call]

The factory manual says 227 ml of oil. It also says the fork oil level is 221 mm. Fork oil type is SAE #15.

As for the edge...I use steel wool!!!

I hope this helps!

Hap

 

[saaz]

Thats a BT45..the way to get rid of that edge is to ride the thing over a lot more and ride harder!! On my GS1000 the BT45s used to look like they had done a 6 hour race they were so ballsed up and chopped out. I think they used to squirm a bit too much.

I have a GT301 Arrowmax at the moment on the back, grips well and never looks lik it is raising a sweat. It does run off the edge in normal riding tho.


I never had a heating up problem for grip with the BT45 front..perhaps you have a harder compound?

 

[robinjo]

The factory manual says 227 ml of oil. It also says the fork oil level is 221 mm. Fork oil type is SAE #15.

As for the edge...I use steel wool!!!

I hope this helps!

Hap

THANKS!!! Steel wool is an option offcourse :wink:

 

[robinjo]

Thats a BT45..the way to get rid of that edge is to ride the thing over a lot more and ride harder!! On my GS1000 the BT45s used to look like they had done a 6 hour race they were so ballsed up and chopped out. I think they used to squirm a bit too much.

I have a GT301 Arrowmax at the moment on the back, grips well and never looks lik it is raising a sweat. It does run off the edge in normal riding tho.


I never had a heating up problem for grip with the BT45 front..perhaps you have a harder compound?

Codes on the tires are 57v on the front and 68v in the rear, I don't know if there are different types if BT45's. The reason I said they need a lot of heat is because to me it feels like it starts to wobble less after some fast (reasonably) corners, I could be wrong offcourse.

I think the tyres are gonna look a lot worse when I get the settings right :twisted: :twisted: :twisted: I have some testing corners wich I take at 130 km/h and the Katana starts to wobble at 110 km/h at a lean angle that doesn't feel extreme to me, nothing dragging . I'll keep you updated.

(this sounds a bit like extreem riding but it's just for testing purposes, I don't ride on the edge or near it in normal driving conditions.)

 

[robinjo]

***Update***

Got the fork oil yesterday, drained and cleaned the forks and put in the oil, 227ml per fork. What do you mean by the oil level is 217mm, how was that measured? The way I know it is with the forks compressed and springs removed but that work. Anyway damping is about right now, sag too (26mm) with the spacer and it handles better but it still weaves in fast corners although as early as before.

Today I ordered some WP progressive front springs, maybe the'll be here on the weekend and then I'll give it another try. Price was about $115. I'm going to take some pictures of the springs that are in there now and the new ones side by side.

b.t.w. WP used too be called White Power Suspension because when they first started in the 70's they could only get a white finish put on their springs, this has nothing to do with racism nor do I want to be affiniated with any form of that crap other than motorcycle springy things

 

[robinjo]

Typing to myself here but never mind :roll:

Use the WP springs with 20W30 oil and a 14mm spacer on top to get the sag at 26mm, they didn't have 15W or else it had to be 10W. Handles much better, cornerspeed on the test track 8) is up from 110 to 130 km/h and my feet made contact with the tarmac 8O on 1 occasion and the chickenstrips are gone, mission accomplished. WP rules :!: :!: :!:

I love my stiff front end...