Looking at buying one, what do I look out for?

[M2004]

Looking at buying this one (and officially joining the club lol, photos attached), listing says , quote:

"BMW K75RTIC 750cc for sale on 56k, this was an ex police bike and has been off the road for a few years in my mate dad's garage he removed all the lights etc. Still has the protective engine/bike Bars around the side.

After a while I bought the bike from him and fitted a new fuel pump and few other bits to get it back on its feet it now runs and rides perfect and looks okay for its age and is complete, however it still needs the brakes looking at the rear caliper was disconnected I think the caliper Pistons were the issue but I'm not entirely sure I haven't looked.

I've realised I'm not going to have the time to finish this as i have other things that have come up and i have to depart with it, this will make a good project for someone as its nearly there or a cheap runner for a cafe racer Conversion etc."

My questions are as follows:
1 What am I looking out for on these bikes/what tools should I take with me to check the bike properly? google has told me driveshaft and input splines, and the ABS (how do I inspect those, and how do i know whats good and whats bad?) How hard is it to change the splines if theyve never been lubed/does the whole driveshaft need changing?
2 If i take it, what work does it need regardless of condition? engine oil, trans oil, brake fluid/pads, what else? are the cluthces hard to change on these bikes?
3 is £500 a good price for it? I have a feeling the answer will be a resounding yes lol

any nuggets of wisdom will be much appreciated, tyia

[Past-my-Prime]

I knew or at least strongly suspected my neglected driveshaft was shot when I would have the bike on the centre stand, in gear, and had a lot of “play” in the rear wheel. To look at the final drive splines, you’ll need to remove the rear wheel, unbolt the final drive from the swing arm, and you will be able to see what is needed. Not a terribly complex job but it does take a bit.

Looking at the bike in question, I don’t see ABS pumps there so that’s one thing you won’t be worried about. Otherwise, if it starts and runs well, you’re in the pink! Change oil, transmission, final drive, and brake fluid, flush the cooling system and refresh, check the valve clearances, and look at the rubber bits (crankcase breather hose cracks and causes poor idle) and the fuel tank innards (maybe replace the fuel filter) and if you’re really feeling ambitions, the air filter.

I think 500 pounds is a good price for a bike that is relatively low mileage and looks pretty good in the photos.

[M2004]

so to check the splines i just check for play in the rear wheel? or is pulling it apart to check still strongly recommended? do i need to check the input splines too?

Not 100% sure I agree on the ABS bit (although maybe im just being hopeful here lol), its a '95 police bike - they shouldve specced it on, no? if it doesnt have it, can I add it on myself (with new components, if theres a kit of some sort)?
How would i check the inside of the fuel tank? remove the pump from underneath and inspect im guessing? and do i need new gaskets for the valve clearances/do i need to check them at 56k miles?

[frankenduck]

There's rotational free play in the wheel with perfect splines. The only way to know the condition of the drive shaft splines is to pull the final drive and inspect the splines. The front splines on the drive shaft don't wear so there's no need to worry about them.




It's not an ABS bike and probably never was. The are no ABS modulators and the peg plates are non-ABS.

It would be POSSIBLE to make it an ABS bike from non-ABS but not at all practical or economical. If you care about ABS then buy a K75 that already has it.

To look in the gas tank: Open the gas cap and remove the four small Phillips screws around the perimeter. Use a good screwdriver and downward pressure to initially break the threads free. If there is corrosion in the threads from sitting then you can strip the Phillips heads of those screws if you're not careful.

The valves on K75s are pretty static so you probably don't HAVE TO check them but it's a good idea to do it for peace of mind. Yes on new gaskets and you probably also want to replace the special rubber washers on the valve cover shoulder bolts as those are very old by now.

There's two theories about buying ex-police bikes:

1) They get abused because the riders don't own them.

2) They are very well maintained because they are part of a police fleet.

At 56K you should not have to worry about the clutch.

It doesn't have a typical solo police seat.

[M2004]

The photos are extremely helpful, ty
so the more worn they are, the sharper the grooves will be (there will be a peak as opposed to a flat portion along the top of the tooth if that makes sense?) - is "some wear" a bad state for it to be in, or does it have plenty of miles left in it? whats their expected lifespan in 2024? in 2000s forum posts people were talking about 100k miles, but nowadays these bikes have been said to last a million kms - is that the case for the driveshafts too, or do they get replaced at some point?

Since these bikes came in an ABS spec from factory, would it not be a case of "remove non abs parts, install abs parts"? (im aware that itll be slightly more involving than just undoing a couple bolts)

for the fuel tank - is the fuel pump attached to the filler cap assembly/top part of the fuel tank? ive removed a fuel pump on a 2018 G310r, the whole assembly came out the bottom - thats all my experience with fuel tank insides...)
Im guessing i'll need to drain the oil before doing the valve clearances - are the rubber washers you mentioned on the outside, between the bolt head and the casing?

sorry for the onslaught of questions.....

[frankenduck]

The "some wear" drive shaft is fine and has oodles of miles on it, easily like 75K if kept lubed. The driveshaft on a well-maintained bike will easily last 100K but they are a wear item and do eventually wear out. I would not go more than 50 miles from home with the bottom one with pointy spikes.

ABS was not standard equipment on K75s, it was an option. ABS bikes have a different main wiring harness so one of the many issues you'd have going from non-ABS to ABS is replacing that along with most of the braking system components and some body parts too. You COULD do it but it would be a huge waste of time, money and effort vs finding an ABS bike to buy.

The gas cap is just a gas cap with nothing attached.

These are the washers for the valve cover bolts.

[M2004]

a new wiring harness? forget it (unless i wire it into the existing harness/add a new ABS circuit, which i could maybe do?) or ill just run the risk of becoming tarmac spread at the first sight of rain - those skinny tyres do NOT inspire grip confidence LOL
I was just looking at the user manual for these  - the ABS switch is blanked out on my example.. that explains that i guess   
how would i access the inside of the fuel tank if the rubbers need changing? or do I need to see the bike in person to understand what you meant with the 4 screws?

I think you guys have given me a rough idea of what im looking at with this bike - i suppose ill update (hopefully with a purchase)

[Past-my-Prime]

Keep your eyes open, they come up regularly, also across the channel in France and Germany — worth a trip perhaps.

I bough mine in Germany, mostly because I wanted to ride around Europe, and then transported it to Canada where registration was pretty straightforward process.

[Laitch]

how would i access the inside of the fuel tank if the rubbers need changing? or do I need to see the bike in person to understand what you meant with the 4 screws?

You don't need to see the Brick in person. When the cap is lifted you'll see the four screws that attach the cap assembly to the tank. Remove the assembly and you'll have a large opening to view the tank and its contents.

Cap open showing two of four screws on perimeter of cap's tank flange.


Cap assembly off.


You don't need to drain the oil to check the valve clearances. The BMW K100/K75 2V repair manual downloadable from this site is at this link. It will help answer many of your basic questions. Download BMW's LE Jetronic training manual from the link in this post and learn how the 2-valve Brick engine management system works.

Check Chris Harris's motorcycle videos, especially the K100 spline lube video. The K100 and K75 have many similar components and procedures.

[frankenduck]

In general, skinny tires have better traction in the wet. They have a narrower contact patch so they are less prone to hydroplaning and they have higher contact pressure to push water out of the way so in general they have better grip in the wet.

Please, please, please buy a bike non-ABS K75 and convert it to ABS. Be sure to post about it here. It will be fun to watch. I have 11 K bikes and enough spare parts on hand and knowledge to convert a non-ABS K bike to an ABS bike for free but I know what's involved and would never dream of doing it. I'd only do it if somebody paid me several thousand dollars to do it.

[Past-my-Prime]

In general, skinny tires have better traction in the wet. They have a narrower contact patch so they are less prone to hydroplaning and they have higher contact pressure to push water out of the way so in general they have better grip in the wet.

Please, please, please buy a bike non-ABS K75 and convert it to ABS. Be sure to post about it here. It will be fun to watch. I have 11 K bikes and enough spare parts on hand and knowledge to convert a non-ABS K bike to an ABS bike for free but I know what's involved and would never dream of doing it. I'd only do it if somebody paid me several thousand dollars to do it.

I’m all in favour of ABS. It’s saved my ass at least twice. But tying to retrofit would not be staightforward at all.

It’s not just all the additional electrical stuff and switches and wires and relays and the brain that sits behind your seat: that would be a pretty fun job. Also, you need to re-route all the brake lines and I imagine the front one that goes all the way to the passenger footpeg area and then all the way back to the forks would have me losing my mind. Lots of weird, tight angles.

[frankenduck]

It’s not just all the additional electrical stuff and switches and wires and relays and the brain that sits behind your seat: that would be a pretty fun job. Also, you need to re-route all the brake lines and I imagine the front one that goes all the way to the passenger footpeg area and then all the way back to the forks would have me losing my mind. Lots of weird, tight angles.

Yes, there's two, not one. One from the front master cylinder to the modulator and another from the moulator back to the front brakes.

I've replaced one of those hard metal ABS lines before. What I did was take off the front wheel then disconnect the frame bolts to the transmission and bellhousing. This allowed me to rotate the rear of the frame up in order get the clearance necessary to extract and reinstall one of those lines. It was an interesting project and less work than disassembling the whole bike.

[daveson]

I'm with duck, if ABS is important, I'd get one with ABS, then I'd make an offer for this one for what it's worth to me, regardless of what it's worth.

One of my thoughts was, if it's only done 56k - why have the front rotors been replaced? That's a question I'd ask. Instrument cluster replaced, probably not, but if the vin is in the add, I'd check to see if the original colour was police white.

Susso, but only a little bit,
Non ABS, susso
Non police side covers, susso
Odo, susso

Two holes where two blue lights would go, goodo.

To me, the K75RT is the pick of the bunch, so I'd put an offer in, regardless of if it's a police bike. I like the look of the bike from the photos, but I don't like the add. He's got the time to half finish it but not the time to finish it, yeah right. If his answers aren't confident you might want to talk about the price.

Some things I look at, engine cold, oil in exhaust, rotors thin, oil around front brakes, water or smoke out exhaust at start up or revs, oil light out quickly at start up, bubbles in coolant, temp gauge behaving, oil and coolant levels in normal range, Speedo and odo working.

[M2004]

could you break down the list you made for checking the bike over? if the speedo/odo dont work is that walk away, or does it depend on the rest of the bike?

[Laitch]

Lubing the clutch hub splines and inspecting/lubing the driveshaft's rear coupling to the rear drive will take room to work, strength, effort, tools, patience, organizational skill and the ability to follow instructions carefully. There are downloadable instructions here and elsewhere for all the tasks I've encountered, along with photos of situations encountered by various forum members throughout the years.

The RT isn't your Honda. It has a complex electronic engine management system where the electrical connectors or components can corrode and oxidize if it isn't run for long periods of time, leaving you chasing your tail trying to solve engine performance problems. One that's been well-used and reasonably stored is likely to be a good runner instead of a problem child.

When you find yourself asking if working on it is going to be "hard", you probably should get something else. It can get complicated. I do all my Brick's maintenance and repair but my satisfaction doesn't come from doing the work, it comes from riding a reliable moto and paying for fuel instead of shop labor.

 

[daveson]

Some say if you find this or that, walk away. I don't, I say well what does that make it worth now. Sometimes if you assume the worst, you won't go too wrong. For example if the odo is a no go, assume it's easily done 400,000. But I'd ask him, how do I know it wasn't a courier and done 800,000?

Just between you and me and the gate post, I like it, I'd happily pay more for it than I think it's worth, cause it's a K75RT. If it rides good, bonus. List the problems you find with the owner, it easily adds up to hundreds. Don't know about prices over there, but if it rides good and the answers are good, I'd be happy to get it for 500. Not so good, or he just wants to get rid of it, maybe try for less.

[caveman]

just sayin, a full service with new skins cost more than 500 bones, hell a few days on the road cost more that 500 bones. Hell a movie and a bit to eat will kill a 100 bones. I will pay 100 bones for the city bags.

[daveson]

True. But see how quickly it gets over 1,000, tyres, discs, suspension, etc. With my brick I said to the previous owner - I respect your asking price but I'm offering 1,000 less which is less than the parts needed, and if I miss out, I've just saved myself a truck load of time.

The city bags look like they used to be white lids, another point towards maybe a police bike.

What year is this brick?

[Laitch]

With my brick I said to the previous owner - I respect your asking price . . .

Translated into American: Your price is too goddam much.

[daveson]

Years ago at work we often used to get machinery in crates from the US. Often a newspaper or magazine was thrown in. It was so funny to read them, they sounded so American. The one I remember the most- if you don't come see me today, I can't save you any money. I even read it with an American accent (Also I've just gotts me a copy of The art of the deal)

[Laitch]

(Also I've just gotts me a copy of The art of the deal)

Stay away from strippers. They'll ruin your art.

[daveson]

Sometimes the magazine was a porno, not too much reading at smoko on those days.

[M2004]

Been away from my pc last day or so, the bike is a '95..

[pinhead]

I knew or at least strongly suspected my neglected driveshaft was shot when I would have the bike on the centre stand, in gear, and had a lot of “play” in the rear wheel. To look at the final drive splines, you’ll need to remove the rear wheel, unbolt the final drive from the swing arm, and you will be able to see what is needed. Not a terribly complex job but it does take a bit.

Looking at the bike in question, I don’t see ABS pumps there so that’s one thing you won’t be worried about. Otherwise, if it starts and runs well, you’re in the pink! Change oil, transmission, final drive, and brake fluid, flush the cooling system and refresh, check the valve clearances, and look at the rubber bits (crankcase breather hose cracks and causes poor idle) and the fuel tank innards (maybe replace the fuel filter) and if you’re really feeling ambitions, the air filter.

I think 500 pounds is a good price for a bike that is relatively low mileage and looks pretty good in the photos.

Unless you love to learn all the mysteries and nuances of the BMW drive system, if the splines are shot its a deal breaker.  Call your local BMW or any MC shop and tell them you have that problem and want it fixed. It would be 2 or 3 times what you are going to pay for the bike.  And I dont believe it is an easy job and is quite common on these bikes to have the splines neglected.  You need to take rear wheel off and drop differential back to inspect splines.  If you dont know how to do that or cant, dont buy it!  These bikes from time to time need repairs.  You better be able to do it your self, else the first time it needs repair and diagnosis, you will have your pockets cleaned.  If you took it to the BMW dealership you would lose your shirt and probably pay more for the repair than the bike is worth.  And these bikes, for whatever reason, are not worth very much.  True you may have to wait to find one, they are really old, now aren't they?  But collectors are not interested in them

[Past-my-Prime]

I was able to find a replacement driveshaft and final drive for a few hundred bucks. The splines were way better than my old ones. The process to change over is not hard, if you have basic tools.
However, its absolutely the case that paying someone to fix an old K will impoverish you unless you’re either already there, of so far from it that you wouldn’t be buying such a bike in the first place.
Which brings me to a question, probably best asked elsewhere: why are K’s so inexpensive to buy, for what (to my mind at least) is such a terrific machine?