Boxerworks.com

Hello! I'm pursuing finding a BMW and am excited to find your forum! Currently I'm the proud owner of a 1964 BSA Bitsa which will stay in the stable but I've been looking for something with a little longer legs for longer road trips.
The question; I test rode a 1984 bmw r100 last week and loved it. However two things raised a question.
1) When the bike is in neutral with the clutch lever pulled in, it didn't want to engage into first gear untill I rolled the bike forward or back a couple inches. Once in gear and rolling down the road it shifted fine.
2) Upon returning to the garage, with the clutch lever pulled in I shifted the bike into neutral. Upon releasing the clutch there was a short grinding sound from the tranny which stopped directly with no movement from the bike.

I should also the mention that the bike hasn't been ridden regularly for the last 10 years and has 75,000 miles. The owners mechanic has been bringing it back online the last couple months. Do you think it's bad news or just needs to be ridden and have the bugs worked out?

Is this model/year a good choice or would I be better off with another?

Thank You much

Welcome aboard.

The 81-84 years are arguably the best....

I'd be concerned about the trannie though.

Putting it into first often requires a feathering of the clutch and the movement helps.

The grinding sound is the worry. Some suggest that 75K miles is about trannie rebuild time.

Welcome, Oldsoul70
I'll add that the input shaft into the trannie needs to be greased occasionally, which requires removing the swingarm and trans. If the shaft was dry of grease for some years then there could be rust there contributing to difficulties.

Yeah, and on a bike this old with this many miles on it, the transmission should be pulled and the clutch measured for wear.
Unless that was part of the "bringing it back online" (documented?), including the all important spline lube.

Hopefully the mechanic adjusted the clutch cable. Didn't the mechanic test ride it?

I have heard that airheads always require some pre-loading of the shift lever when releasing the clutch. I never really noticed it, myself, but maybe I had (long story) a good transmission.
Regardless, it sounds like yours is having more difficulty than it should.

Ask to drain the gear box lube and examine the magnet on the drain plug. Big pieces - BAD! Small, smooth fuzz - normal.

At that age, the heads are the other thing that could need some work. They may have already been rebuilt.

The clutch lever should have a little freeplay. It may be clutch adjustment.

Since you're thinking of buying that kind of bike, I'd recommend buying a Clymer's manual. They are very thick and are available used or new. Armed with that manual, you could check the clutch adjustment.

Chuey

Thanks for the input! So if I understand correctly the shifting into first with rolling is fairly normal however obviously the grinding is a concern. I did meet the mechanic and he has a good name around town but he probably just rode it around the block.I should talk with him personaly.
Rob, I know the owner would be cool with me draining the tranny lube. What oil and amount should I bring to replace it? If the magnet looks fine should that ease my mind as far as deep tranny isues?
Airbear, Would rust on the input shaft be something that would clear up with some use or something to address right away?

The owner is asking $3200. In my area beaters are selling for $2500 and creampuffs for $5000. Maybe I should try and get him to $2500.

Thank you again Fellas!

I don't think $2500 is an unreasonable target for you to shoot for with the tranny concerns. A used transmission will $400 - $500, plus the work to put it in.

If the magnet looks fine, it could be that the mechanic cleaned off any large stuff that MAY have been there. It really depends on how many miles (ks?) it has gone since it's last change.

Something in the neighborhood of a 90 weight gear oil should be fine. It comes in a number of formula ratios from straight petroleum/mix/straight synthetic. I've been using synthetic for the last 10 years, or so - usually a mix.
Opinions on lubricants are quite varied, you will find. I use straight petro for my engine because the high pressure system of the engine tends to push the synthetic past gaskets and seals. Again, YMMV. (Your mileage may vary)

Oldsoul, an old bike that has sat for a long time will require some checking over. Mine was very much an unknown quantity when she adopted me about 8 years ago. I have had a lot of fun and spent a bunch of dollars going through all the mechanicals, replacing bits as required between riding good long trips. If you are inclined to work on your own machine I can (almost) guarantee you a lot of satisfaction as you get to know your bike. If you have to pay someone else to do the work, you might be better off waiting for an excellent low miles example. I assume you are in the US, where old boxers seem to be almost disgustingly inexpensive. Lucky bastards.

Yes, do get to know the local mechanic. You are fortunate indeed if you can develop a good relationship with someone who knows these old darlings. Put him/her on your christmas card list.

Either way, I'd get a copy of the Clymer manual and settle in here at Boxerworks (pull up a comfy chair and grab something to drink). I can promise you will be educated and entertained.

I will second everything AirBear said.
It took me a couple of years to get to know everything about my R100.
And yes - some money to replace and or upgrade stuff (it's still going on).
For me personally, I could not afford to pay for everything to be done by a mechanic. But in any case, I prefer to do it myself 'cause then I know what's what. (I did pay to have a valve job done.)

A good hint for an older bike is to suspect everything that is rubber. It degrades over time.