BMW K bikes (Bricks)

You are not connected. Please login or register

View previous topic View next topic Go down  Message [Page 1 of 1]


1Back to top Go down    Air Filter Replacement (needed)? on Wed May 02, 2018 10:38 am

George_Pap

avatar
Silver member
Silver member
Hi all
Just finished most of the resurrection works on my K100RT (early 1985) that was idle for more than 8 years.
Satisfied so far , took her for a couple of short rides almost 200km put on it since past Monday.
One of the things i didnt change is the air filter.
Read a lot about air filters, etc and i m between a Bosch Air filter and a KN BM2605 one.

As i see from my notes the last time i changed the filter was at 100.000km (2001) and now i m at 108.000

Mechanic ( which i dont trust ) said he checked it and it's fine just cleaned/lubed it but didnt changed it.

Should i change it?

What is a typical symptom to indicate changing? Bike responds very positive to any gas twist in the whole rev range.


__________________________________________________
K100RT (Early 1985 -nonABS)
    

2Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 11:03 am

92KK 84WW Olaf

avatar
Life time member
Life time member
They last well but are paper filters so you don't lube it so I am not sure what he says. 8,000km would not mean you need a new one. My only concern is if the mechanic did actually check it but that's easy to do. My own thought is after 17 years to get a new one but not bothered about a Bosch one, lots of others will work fine and they are easy to fit once you know how.


__________________________________________________
1992 K100LT 0193214 Alaska Blue 101,000 miles
1984 K100RT 0022575 Baja Red bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Mystic Red 58,645 now 69,000 miles
    

3Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 11:06 am

Inge K.

avatar
VIP
VIP
What kind of filter is in the bike now?

If the mech said he have cleaned and lubed it it's probably a K&N or similar
which shouldn't be changed....only cleaned and oiled.
The negative side is that it lets more dirt through than the original paper filter.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

4Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 11:15 am

George_Pap

avatar
Silver member
Silver member
Thank you both Smile
Have no clue what's inside that box. I'll give it a check this afternoon and post some pics. I doubt its a KN one. He would have mentioned.
So if its a paper one goes to the recycle bin. If its a fibre based KN or such stays.

Cool


__________________________________________________
K100RT (Early 1985 -nonABS)
    

5Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 11:33 am

92KK 84WW Olaf

avatar
Life time member
Life time member
You live in a very dry climate with means a lot of dust in the air filter. IngeK mentions how the K&N lets more dust through.....think I would be putting in a paper one.


__________________________________________________
1992 K100LT 0193214 Alaska Blue 101,000 miles
1984 K100RT 0022575 Baja Red bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Mystic Red 58,645 now 69,000 miles
    

6Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 11:41 am

George_Pap

avatar
Silver member
Silver member
@92KK 84WW Olaf wrote:You live in a very dry climate with means a lot of dust in the air filter. IngeK mentions how the K&N lets more dust through.....think I would be putting in a paper one.
Copied that Smilei'll try my best to find a paper one. The plus for KN is that its readily available .
Thank you !
Breathing looks and sounds fine on the lady so far. Only complain is that for a couple of times when starting up i get something like poor mixture indication. Idle struggles to keep steady, after little choke play goes back to normal. But this happened yday after 4 hours of leaving the bike in the garage with air temperature around 30 C so its not justifying this behaviour.


__________________________________________________
K100RT (Early 1985 -nonABS)
    

7Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 1:00 pm

Point-Seven-five

avatar
Life time member
Life time member
If I found a K&N filter in the air box(found one when I got one of my bikes) I would bin it immediately. They don't offer any performance benefit and let in a lot of dirt compared to paper filters.

With a paper filter there are two checks I do. Tap it on a clean piece of paper, does any dirt shake out? Can you hold it up to the light and see light coming through between the folds? If dirt shakes out or you can't see any light, you need a new filter.


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

8Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 1:09 pm

duck

avatar
Life time member
Life time member
Another issue with oiled air filters is that the oil gets "cooked off" more quickly than with most engines due to where the air filter sits and the heat it gets exposed to so you need to cut the recommended filter maker's maintenance cycle by half or so. So aside from letting more crap through it also requires tons more maintenance than a paper filter.

Also the size of a K filter is HUGE for a 1 liter engine so the BMW service interval of 12,000 miles is silly. I change every 50,000 miles and even that is overkill.

WIX makes a K air filter which I think is where BMW gets them.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

9Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 1:16 pm

George_Pap

avatar
Silver member
Silver member
@duck wrote:Another issue with oiled air filters is that the oil gets "cooked off" more quickly than with most engines due to where the air filter sits and the heat it gets exposed to so you need to cut the recommended maintenance cycle by half or so. So aside from letting more crap through it also requires tons more maintenance than a paper filter.

Also the size of a K filter is HUGE for a 1 liter engine so the BMW service interval of 12,000 miles is silly. I change every 50,000 miles and even that is overkill.

Understood Smile
If we assume that in my case its a paper filter. Problem is not the mileage, its less than 8000km but should i be worried for the 18 years of its life in that box?


__________________________________________________
K100RT (Early 1985 -nonABS)
    

10Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 1:22 pm

duck

avatar
Life time member
Life time member
@Point-Seven-five wrote:If I found a K&N filter in the air box(found one when I got one of my bikes) I would bin it immediately. They don't offer any performance benefit and let in a lot of dirt compared to paper filters.

With a paper filter there are two checks I do. Tap it on a clean piece of paper, does any dirt shake out? Can you hold it up to the light and see light coming through between the folds? If dirt shakes out or you can't see any light, you need a new filter.

You can also clean a used paper air filter some by vacuuming the input side or blowing air on the output side. If you have it out to check that costs nothing.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

11Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 1:32 pm

duck

avatar
Life time member
Life time member
@George_Pap wrote:
@duck wrote:Another issue with oiled air filters is that the oil gets "cooked off" more quickly than with most engines due to where the air filter sits and the heat it gets exposed to so you need to cut the recommended maintenance cycle by half or so. So aside from letting more crap through it also requires tons more maintenance than a paper filter.

Also the size of a K filter is HUGE for a 1 liter engine so the BMW service interval of 12,000 miles is silly. I change every 50,000 miles and even that is overkill.

Understood Smile
If we assume that in my case its a paper filter. Problem is not the mileage, its less than 8000km but should i be worried for the 18 years of its life in that box?

In theory in an extremely moist climate that can cause the filter fibers to swell over time. But that's theory. In real life that's nothing to worry about.

If I were you:

1 - Current filter is oiled type: Clean/reoil it until you can obtain a paper one.

2 - Current filter is paper. Use it and worry about something else like using synthetic blinker fluid.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

12Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 1:37 pm

George_Pap

avatar
Silver member
Silver member
@duck wrote:


2 - Current filter is paper. Use it and worry about something else like using synthetic blinker fluid.
Very Happy Very Happy Very Happy


__________________________________________________
K100RT (Early 1985 -nonABS)
    

13Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 1:40 pm

Point-Seven-five

avatar
Life time member
Life time member
@duck wrote:2 - Current filter is paper. Use it and worry about something else like using synthetic blinker fluid.

affraid Oh no, not another blinker fluid thread!!!


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

14Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 3:30 pm

George_Pap

avatar
Silver member
Silver member













In the last one you can see it as it was mounted from right side of the bike.

It looks fine to me.

Sent from Topic'it App


__________________________________________________
K100RT (Early 1985 -nonABS)
    

15Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 5:55 pm

Point-Seven-five

avatar
Life time member
Life time member
Put it back in. Make a mental note to look at it again in 5 years or 80,000 km.


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

16Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 5:58 pm

George_Pap

avatar
Silver member
Silver member
@Point-Seven-five wrote:Put it back in. Make a mental note to look at it again in 5 years or 80,000 km.

Hahaha! All right!

Sent from Topic'it App


__________________________________________________
K100RT (Early 1985 -nonABS)
    

17Back to top Go down    Re: Air Filter Replacement (needed)? on Wed May 02, 2018 11:26 pm

Inge K.

avatar
VIP
VIP
@George_Pap wrote:


In the last one you can see it as it was mounted from right side of the bike.

I hope it's not like that.....the side that is shown in the last picture should
point to the rear of the bike.

I wonder which filter your mechanic lubed.....


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

18Back to top Go down    Re: Air Filter Replacement (needed)? on Thu May 03, 2018 4:41 am

George_Pap

avatar
Silver member
Silver member
My mistake, during the upload Inge, the previous photo shows the visible side of the filter.
As for the mechanic.. I m actually glad for the final outcome. If it wasn't him i wouldn't have learn all these about my bike!
I feel much more confident now about it's operation and state , sure, I need to learn a lot more in the future but it feels great to know the most about your bike, especially if it's a granny like my K .

Sent from Topic'it App


__________________________________________________
K100RT (Early 1985 -nonABS)
    

View previous topic View next topic Back to top  Message [Page 1 of 1]

Permissions in this forum:
You cannot reply to topics in this forum