The 650 Dakar Thread

[pyrate]

Originally Posted by voomvoom

http://f650.com/phpbb3/viewtopic.php?f=30&t=225753

Hiflo filter, $3.71

Since an o-ring is not included, can you find that easily some place else?

[WU7X]

Originally Posted by JDLuke

On the oil window: That thing does not give you correct readings most of the time. In order to check the oil level, you have to warm the bike up to operating temperature (wait for the fan to come on) and then shut it off and wait for one minute. Then and only then can you check that the oil level is in the middle of the sight glass.

Does that sound stupid? It sounds that way to me, too, but that is, I suppose, part of the price we pay for the dry sump system.

Remember to let your machine cool off overnight (or equivalent) before checking valve clearances. I usually strip the bike down to the top end at night and then check the valves the next morning.

Hey JDLuke, Thanks! now I realize that I'm not totally daffy and losing it all in my dottage.

Can you tell me something about the shims? Are they a standard size that I can find locally, or do I have to go through a BMW dealer to get them? I'd like to find a box of them like the guy in the ChainGang DVD has. I can't imagine getting everything pulled apart and then having to wait a couple of weeks to get the correct shim size mailed to me.

[Uhuru]

Originally Posted by pyrate

Is the wheel a 19" or are you going to a total height of 19" including the tire? I have a 21" wheel with TKC-80 tire and then a 19" wheel with a street tire. The total height of the wheel/tire combo for each setup is the same (the street tire is just taller than the dirt tire) therefore it doesn't change the overall height of the bike so no issue with the sidestand etc.

Thanks. I'm looking at buying and installing a 19 inch rim and a 19 inch tire.
If the total height of the wheel/tire combo doesn't change going from a 21 inch rim to a 19 inch rim, as you state, it sounds like there would be no difference in handling, assuming the tires were the same design, but somehow that seems wrong to me, with a 2 inch shorter diameter rim. Now I'm really scratching my head. Anyone able to help me understand?

[pyrate]

Originally Posted by Uhuru

Thanks. I'm looking at buying and installing a 19 inch rim and a 19 inch tire.
If the total height of the wheel/tire combo doesn't change going from a 21 inch rim to a 19 inch rim, as you state, it sounds like there would be no difference in handling, assuming the tires were the same design, but somehow that seems wrong to me, with a 2 inch shorter diameter rim. Now I'm really scratching my head. Anyone able to help me understand?

21" Rim with dirt tire, with a shorter sidewall, will rely more on the rim for stability. The stiffness of the sidewall will have less effect overall.

19" Rim with street tire, with a taller sidewall, gives a bit more because of the sidewall of the tire. Depending on your choice of tire and how stiff the sidewall will make all the difference in the world.

[pyrate]

Originally Posted by pyrate

21" Rim with dirt tire, with a shorter sidewall, will rely more on the rim for stability. The stiffness of the sidewall will have less effect overall.

19" Rim with street tire, with a taller sidewall, gives a bit more because of the sidewall of the tire. Depending on your choice of tire and how stiff the sidewall will make all the difference in the world.

Compare it to a low profile car tire on a large wheel vs a baja high profile tire on a smaller wheel. Both can have the same overall height but use a different combination to get there. The stiffness of the sidewall on the higher profile tire will determine the handling. But overall height is the same. Does that help? If not, I will try to get my street tire down and take a picture of it next to the dirt wheel and tire and give a better bike example.

The big difference would be if you went with a super motard kind of set up where the front and rear wheel are the same size with the same size tire. That will change things dramatically.

[Uhuru]

Thanks, Pyrate, I get your explanation about low profile tires and dirt tires, but...what if you had, to be specific and avoid confusion, a new 21 inch Metzeler Tourance tire on a 21 inch rim and you want to compare its total height and performance to a 19 inch Metzeler Tourance tire on a 19 inch rim? That is the part I don't get...the overall tire height isn't still going to be the same, is it?

[JDLuke]

Originally Posted by WU7X

Hey JDLuke, Thanks! now I realize that I'm not totally daffy and losing it all in my dottage.

Can you tell me something about the shims? Are they a standard size that I can find locally, or do I have to go through a BMW dealer to get them? I'd like to find a box of them like the guy in the ChainGang DVD has. I can't imagine getting everything pulled apart and then having to wait a couple of weeks to get the correct shim size mailed to me.

Oh, I never said you weren't daffy...

Anyway, the shims... I honestly don't know. I have been fortunate enough to never need to change one yet. I bought the chain gang valve check kit, which included a small selection of shims, and only hope that if I need one it will be there.

Since the engine is a Rotax, I suspect that obtaining shims from a snowmobile dealer or something would be very possible. I just have no experience with doing so.

[BMacW650]

Originally Posted by Uhuru

I love my 2005 Dakar and don't want to sell it, but I find that I'm now enjoying longer trips, essentially all tarmac. So, I'm interested in understanding the pros and cons of using a 19" front rim and tire on this bike. 19" seems like it would be better for those long two lane highway trips than the 21". I would keep my 21" rim and tire.

I'm thinking there may be sidestand problems created with going to a 19 inch front tire and rim, but would this change require a shorter sidestand? Can I expect notably improved handling on twisties and highways with a 19" front wheel? What else is involved, what should I be thinking about on this?

What's wrong with your 21 inch on a long trip? Do you have any complain so far? Most of the highways in US are straight. Unless you are taking your bike supermoto style and do a lot of twisties and tracks, I don't see why you can't live with the 21 in rim? You will probably get better handling if you drop the fork and rear shock. But hey what's why you have a Ducati for, right?

[Uhuru]

Originally Posted by BMacW650

What's wrong with your 21 inch on a long trip? Do you have any complain so far? Most of the highways in US are straight. Unless you are taking your bike supermoto style and do a lot of twisties and tracks, I don't see why you can't live with the 21 in rim? You will probably get better handling if you drop the fork and rear shock. But hey what's why you have a Ducati for, right?

Absolutely, the Monster is a blast to ride, but think of a 300 mile ride bent way over on it and you'll get why it's for shorter rides, at least for me.

Forget most of the highways in the U.S., I live in Colorado, so mountain roads are where I ride. Think needing to make many very tight 10-15mph turns climbing up to a mountain pass--that is what is common where I ride. (I know, I know, this is a GREAT problem to have). A favorite ride of mine, Trail Ridge Road, is over 12,000 ft. This is what makes me think a smaller 19 inch front wheel would be more nimble than the 21 inch stock, thus better for my kind of riding.

[voomvoom]

I just re-re-re-re- use the o ring and anneal the copper washer. donno if its considered as bad practice, but its sure frugal

Originally Posted by pyrate

Since an o-ring is not included, can you find that easily some place else?

[pyrate]

Originally Posted by Uhuru

Thanks, Pyrate, I get your explanation about low profile tires and dirt tires, but...what if you had, to be specific and avoid confusion, a new 21 inch Metzeler Tourance tire on a 21 inch rim and you want to compare its total height and performance to a 19 inch Metzeler Tourance tire on a 19 inch rim? That is the part I don't get...the overall tire height isn't still going to be the same, is it?

If you were to buy the exact same tire brand and model for two different wheel sizes then yes I would have to say that the overall height might be different (trying to check with a tire guy now).

My bikes previous owner obviously thought of this and when purchasing the 19" front wheel and tire, bought a tire sized in such a manner that it is the same exact overall height.

I would never buy the same exact brand/model tire for a 21" and 19" wheel (Metzeler Tourance for example) because it would not make any sense for my use to do so. When I have the 21" wheel on the bike I am more prone to ride in the dirt so will run the knobby TKC-80. When I run the 19" it is for street use so would run the street Metzeler for example. So I guess I have never made the comparison you are trying to do running the same type of tire for both wheel sizes (i.e. - 100/90-19 & 90/90-21 Metzler)but rather run two completely different types of tires but keep the overall diameter of wheel and tire the same.

Clear as mud?

[pyrate]

Originally Posted by voomvoom

I just re-re-re-re- use the o ring and anneal the copper washer. donno if its considered as bad practice, but its sure frugal

okay...just am not a fan of leaks and breakdowns so usually would spend the few extra bucks to get all new items if I can.

Thanks for the response.

[Uhuru]

Originally Posted by pyrate

Clear as mud?

Actually it is clear. Thanks.

[dang]

voomvoom

good on you for annealing the washer. Look around Adv a little and you'll see people get pretty freaky about only using new parts though. When I trained for my aircraft mechanics license in the 70s we were allowed to anneal copper washers. Dunno about o-rings though. Oddly reusing them wasn't recommended but you could make them from a roll of stock with superglue. Go figure.

[Gravel Seeker]

Originally Posted by pyrate

Since an o-ring is not included, can you find that easily some place else?

I usually don't change o-rings nor crush washers when changing the oil. I've never had a leak.