Donít Ask: Dirt Bike Tech Questions Answered (Jan. 2011)

Jan. 03, 2011 By Rick Sieman
Got questions for Rick ďSuperhunkyĒ Sieman? Send questions to [email protected], and make sure you read the rules below:


If you choose to email a question to this forum, then you must conduct yourself accordingly. Therefore, the following rules are in order:

1. Do not write your email to me IN CAPS. If you do so, I will print out your question and do terrible things to it.

2. Do not request a personal e-mail response. Since I get thousands of questions each month, trying to answer them all would cut deeply into my leisure time, which I value more than your current state of confusion.

3. Try to spell at least in a semi-correct fashion. If you choose to mangle the English language, expect no mercy from this quarter. You might be mocked severely.

4. Do not ask for me to send you copies of my many manuals and literature. I am not in the library business, nor do I want to spend the bulk of my day at the copy machine just because you're too lazy to ask your dealer,  or look around a bit.

5. Don't bother me with truly stupid questions, like how to get 50 more horsepower for a buck and a half

6. Now that you know the rules, think carefully and have at it!
Oh yes Ö Iíll leave your e-mail unedited, for what itís worth.

Previous Donít Ask Dirt Bike Columns:

December 2010

November 2010

October 2010

I have a Yamaha CT1 2-stroke that I'm converting to just a dirt bike. I want to strip all the wiring to the minimum I need to ride the bike in the dirt: no lights, no key, no battery (if possible); just the bare ignition system wiring I need. My question is: do I need a battery and rectifier? I would like minimal wiring-just what I need to kick and go. Can I wire the magneto, points, and condenser directly to the spark coil without the battery? I've run the bike with a dead battery, so I know it can work that way, but I don't know if I can strip it out.

Connect the lone black wire that's right next to the top coil on the top frame tube, under the gas tank, to the hot side of the coil and you will be connected right to the magneto, and it will bypass the rest of the wiring harness. You really should have known.


so I took my 17 yr old son to a swap meet/vintage track race at PIR. watched the races on the dirt and tarmac. well he caught the bug bad to race the 250 and under two stroke vintage class on the road.  we promptly pulled a 76 mr175 from out behind a coworkers shed, washed off 13 years of dirt, leaves and birds nests and started stripping it, chopping it, and building it into a cafe racer. LOTS of work later we've got the parts out to paint and ready to put it on the road. my question is, because the motor/gearing is set up for off road use, what would be the best modifications to do to get it rippin to it's fullest potential on the street? will the mr250 top end cinch up to the 175 bottom end? thanks so much for your input and as always I look forward to reading your blog.
Stephen Martzholf

Unfortunately, the MR 175 motor is based on the 125 Elsinore bottom end. This means that you can't put the 250 top end on that particular set of great cases. If you want to ride the 175 on the street, youíre going to have to go about two teeth more on the counter shaft sprocket to get the bike to operate right at cruising speeds.


I'm an owner of a 1973 honda mt 250 elsinore, all original very clean would no the apox. value of this bike.
Thank you

If you had a 73 Elsinore motocrosser, you'd be in great shape, as these bikes are highly sought after as collectors and draw big money during resale time if they are in perfect condition. Iíve seen the motocrossers go for close to $5000 bucks for good examples. The MT, on the other hand, is nowhere near as desirable as collector bikes go. There is not a crowd of people beating each other with clubs to get MT 250s. If you have a real nice example of one, maybe, just maybe, you might get somewhere between 800 and 1200 bucks for it. However, you're going to have to find someone who really wants one of these.

i have a early 70s intermedaite 80cc rupp minibike that runs and in good shape looking to sell but dont know what to ask for it anyone thatcan help

I'm not a minibike fan, but there are a large number of collectors out there who go bug nuts over the older minis. My guess is that if you have a Rupp 80 in very good shape it might go for $700 or $800.


Hello there
I have a 1971 Honda XL 70 in excellent shape and I was woundering if you could give me some type of an idea what this may be worth and I also have 1973 Honda St 90 semi automatic also in excellent shape and again I'm looking to get some type of idea what this may be worth today..

I would appreciate any type of info you could give me

This is one of the most sought-after minibikes made, and a whole lot of writers learned on these machines. If you have a pristine example of an XL 70, you might be looking at as much as $1500 for it. Of course, and XR of the same year would draw much more money if it was flawless.


Hi Mister Hunk,
I got a 1981 Maico 490 that my uncle just gave to me.  He donít ride anymore so itís a freebie.  The bike runs but is pretty rough looking.  The front fender is cracked and all of the other plastic is all scratched up bad.  And the cover on the saddle is cracked and torn.  It sat outside for a  few years so all the color is also faded.  It does start OK and does run.  The tires are shot.  So should I sell this thing or keep it?  And if I sell it what should I ask for it?
LA, Calif.

The Ď81 Maico 490 is one of the most sought-after vintage racers around. I've seen clean examples of this bike go for as high as $10,000 and highly refined 490s with scads of Wheelsmith goodies go for even more. If you feel like going vintage racing, by all means make the bike look better for a few hundred dollars and go through the mechanics of the machine to make sure it's going to hold up, and then go racing. If youíre not going to go racing, make the bike look good with fresh plastic all the way around, a new seat cover, fresh tires and some careful attention to detailing and youíre going to get $4000 or $5000 for it.


Good afternoon "Mr. Dickhead",
I couldn't help but notice that your enlarged cranium is a bone sack for useless and offensive sarcastic comments. I am uncertain if you went to Prick college to aquire such talent, but you seem to have graduated just fine. If you and I were the last two people on earth, I would not ask you to help me, even if I were on fire.

You insult people for their speech, country, lives, and existance. I wonder if the cause of your bitterness and distasteful slander to others is a result of your own self loathing, or were you simply born to pour vomit from your mouth upon others.

Thank you for your time, I look forward to further discussion, also you have been such a "huge help" that you should get a cookie.

My dear Regina, why don't you just take the cookie and place it where the sun don't shine. The reason I give sarcastic comments to certain e-mails is because they don't even try to communicate like a human being. It's one thing to misspell, have a typo or two or three, or even fail to capitalize, but when your entire e-mail is a pigsty of sloppiness, I have no room for that. People who send in trash expecting an answer get back another form of trash from me. I don't expect perfection, but I expect people to at least try. In this day and age of letting crap slide by and trying to make excuses for everyone's failures, I feel that DON'T ASK is a beacon of light. If you would rather not find out the truth about things, by all means continue to wallow in that pigsty that I pointed out. Now go away please don't bother us anymore.  By the way, please note that I did not rag on your few typos.


thank in advance .
I have a 82 cr480r a two stroke monster. when i bought it ,it was not running do to no stator or rotor . i have since goten thoughs parts but now i am being told that the stator has to match the CDI ? well there are no markings on the CDI. So is there a way to find out this info without spending a butt load of money ?? Any info would be great
Steve Rankin

Every CDI I have ever seen has had some markings on it to identify what it is. The markings are usually in the form of some sort of plastic or metal tag on the CDI box itself, or small numbers stamped into to the metal box. Perhaps the ID tag was painted over. When you bought your parts for your bike, did you ask the person or the company you bought it from if it was for an Ď82 or and Ď83 480? At this point, my recommendations to you would be to hook everything up and see if you get spark. If you get spark, youíre home free. By the way, the Ď82 and the Ď83 480 are identical in the electrical department.


Why is it that you always rag on the YZ Yamaha 490? I've had one of these for about a year now, and most of the time it runs pretty damn good and strong. The only problem I have is when it's cold out it runs good but the minute it gets warm it sort tends to run a little rough. But I tell you what, that thing is nothing but fast. I race it against my buddies CR 450 Honda in we were just about side-by-side in a regular drag race. And this bike is only two years old and mine is pretty old. So I'm going to ask you again why you rag on the YZ 490 so much?
No Name Given

I learned to really hate the YZ 490 when I raced it in two 45-minute motos at Saddleback Park back in the day. The bike was indeed very fast, and I got two good starts because of the power, but it faded quickly as the bike proceeded to beat me to death. In the morning when it was cool, the bike ran great. When it got warmer, the jetting started to blubber. As it got hotter, the bike ran worse and worse and worse. At the end of my two 45-minute motos, the calluses were pulled off of both hands from the horrible vibration of the bike. I loaded the bike up on the trailer and refused to ride it again. Any bike that would do that to you doesn't deserve to be produced.


I got into an argument the other day with a friend of mine and he said that the new Honda 250 racer was under 200 pounds. I told him no way was that right and that there's never been a 250 ever made that weight under 200 pounds ready to ride. Your input on this bike saved me a few bucks in our bet.

I hate to be the one to break it to you, but the OSSA Phantom made in 1974 was under 200 pounds ready to race. The motor in that fantastic bike only weighed 53 pounds. Compare that to over 70 pounds for modern four-stroke offerings. As far as your buddy having CR 250 Honda weighing in under 200 pounds, that's a joke. The bike is closer to 250 pounds than it is to 200 pounds, and that's a sad fact. As far as I know, the OSSA was the only production 250 motorcycle that tipped the scales under 200.


Gary BaileyIíve been racing for almost a year now and have yet to get a good start. I have Honda CRF 450 at its eight 2008 model in good shape, but when I race not only do all the other bikes beat me to the first turn but all the other Honda 450 do it as well. Is there some secret I don't know or something I should be doing that I ain't doing? I sure like to get a good start at least once in my life.
Martin Wilson

I used to get poor starts too, until I went to Gary Bailey's motocross school way back in the day. Gary taught me the secret of getting a good start. Always use second gear when starting, keep the throttle steady at a higher RPM, and don't ever let the clutch all the way out. When you go over the starting gate, and if the front and tends to come up, pull the clutch in a little tiny bit and don't back off throttle. I never fully released the clutch until I got out of third gear, even on long starts. Once I started using Gary's technique, I started getting holeshots on a regular basis. I also made sure that the rear tire was fresh and had fairly low pressure in it, anywhere between 10 and 14 pounds, depending on the terrain.


Get the first four years of DIRT BIKE Magazine on discs. Those early copies are getting hard to find and the ones in the first year (1971) are going for big bucks. Hereís what you get:

*   Every issue from June of 1971 through all of 1974. That June í71 issue was the very first issue. I worked on all of these magazines until that last issue in 1974. Youíll see a big difference in content in that last issue and the ones that preceded it.

*  Every issue has every page included. All the color pages are reproduced in color. You can print out every page if you want to, since the issues were produced in Picasa 3 format.

*  Or you can put it in your computer (or CD/DVD player) and simply enjoy a slideshow of each and every year. There are seven discs included in the package. Each disc contains one-half of a year (six issues) in order. This comes to about 4400 pages total.
Hereís how to work the discs: Pop a disc in your computer and open it. An icon saying PICTURES will appear. Left click it.

Another icon will appear naming the disc (ex: DIRT BIKE 2nd HALF 1974). Left click it. This will bring up a bunch of dates/icons. Left click on the first one.

This will open up Picasa 3 and the first page of the magazine. Go to the bottom of the photo with your cursor and this will reveal the tool bar for Picasa 3. Itís self explanatory. You can make the page bigger or smaller, rotate the page, edit the page in Picasa, advance to the next page, make a slideshow out of the magazine by clicking the arrow in the middle, or simply print the page out by going to the down arrow (far right), click it and follow the directions.

The seven disc set costs $70 plus $5 for priority mail.  So get your very own piece of history.   go the STORE for  details. Newsletter
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