Rick Sieman Answers Your Off-Road Dirt Bike Tech Questions

Sep. 07, 2010 By Rick Sieman
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.
                                              
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SUBJECT:  WEIRD SHIFTER?
Re: shift-level-seat-replacement. Thanks for the write up, it will help me alot. I am not the best at this stuff mostly because I am a newbie at it (18 Years young) But I really appreciate it. My shifter literally will turn clockwise and counter clockwise, which I know is not good But I am hoping this is what the problem is. I am going to have to re-read your write up a bunch of times so i dont mess up!
thanks again
No Name

This is one of the strangest e-mails I've ever received. Not only do you not tell me what year and model of bike you have, but your description of what's happening to your shifter borders on beyond bizarre. I can only assume that the splines on the shift shaft are completely stripped and your shifter is rotating freely. Before you go nuts, it might not hurt to see if the bolt holding the shifter in place is tight or is even there. Good luck. You're going to need it.


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SUBJECT: ANOTHER WEIRD SHIFTER PROBLEM
When I shift my 2001 yz 125 out of first into all the other gears it sounds and feels like it is in the same gear.
Jacob Ponder

That's probably because this bike is staying in low gear and not moving to the next gear up. You can check this by putting your bike on a stand and finding neutral in the gearbox. Then push down on the shifter one click to get a lower gear. Now push up on the shifter again and you should get to neutral. Then push out one more time and it should be second gear. Keep pushing up on the shifter one click at a time until you get all the way to top gear. Now take the bike off the stand, start it up and ride up the street very slowly, taking your time to go through the gears. If it doesn't engage in the upper gears as you ride, chances are that a spring has fallen off the shifter pawl and that means taking off case cover and finding out what the problem is.

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SUBJECT: WHICH BIKE TO GET STARTING TO RIDE AGAIN
i am 13 and looking to get back into dirtbikes. What are the pros and cons of a 2003 dr-z 125 that is brand new i am thinking about buying one just for trail riding.
thanks
Mark Costner



The Suzuki DRZ 125 is a mild-mannered trail bike with not a lot of power, a less than average suspension, and is built primarily for young or short riders. If you are experienced, chances are that the DRZ 125 will bore you to tears after a very short period of time. However, if you just want to go casual trail riding, itís probably a fairly good choice.

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SUBJECT: HONDA CR 250 WON'T MOVE
i have a 2000 cr250 was riding and it strated to back fire then stalled now my kicker is stuck it wont move at all
Shawn

If your kick starter won't move at all, chances are you have seized the top end tighter than Chelsea's nuts. Whenever it started backfiring and then stalled, that's when the top end started leaning out and literally became a one-piece metallic decoration. This now means that you have to take the top end apart and freshen it up. However, based on your e-mail, it's probably far beyond your limited skills. Take it to a shop.

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SUBJECT: WHICH OIL FOR A HARLEY?
what type of two stroke oil is best for a 1976 sx 175 harley? I used boat and jetski two stroke and I leave a smoke cloud eveytime i shift.
thanks
Dan De Young

In my personal opinion, the 175 Harley SX is a real pile and would definitely benefit from a nice mixture of water and Portland cement instead of oil. That way, it wouldn't run any more. Since you insist on riding this pathetic little Italian motorcycle, you couldn't go too far wrong with Yamaha R at 32 to 1 ratio. Sorry to be so cruel about your Harley, but that's how I feel.

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SUBJECT:  MY HONEST OPINION OF THE KAWASAKI KLX 300
Re: Performacne KLX 300 modifications
Im considering buying a 2001 klx 300, its a great deal but when you tack the bike up, it bike just dies. Could this be a clogged fuel line, sludge in the carb, a dirty air filter or something else? any insight would be appreciated.
JR

In my humble opinion, the entire KLX line by Kawasaki is far below average. A good friend of mine spent a small fortune modifying and building up a 300 DLX, and my 20-year-old KDX 200 would still run away and hide from this bike. If you haven't bought it yet, don't.

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SUBJECT: YAMAHA VINTAGE DIRT BIKE ID GUIDE
Could you please tell me the year, model,and cc from this serial # 371-016633.
Thank you, very much.
Dario

Your request for model ID that you told me had me halfway up a wall. I looked in all my material and could not find what kind of bike you had. Then, on impulse, I checked in the street bike section and the numbers you gave me indicate that you have a 1973 TX 500 A or B.  This is a twin cylinder, 8 valve street bike and may be a Canadian model. Just in case your eyes are failing you, the name of this site is Off-Road.com, not Street-Road.com. Now go away.

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SUBJECT: HONDA PIPE CORE PROBLEMS
i have an aftermarket silencer on my 250r..i went to repack the silencer (which it needed badly) and the problem is i can't get the core out. There are three allen screws on the backside/spark arrester and the front- that ties into the pipe- is just welded. So i pull and twist and cannot get the core to budge...is this type of silencer not re-packable or am i missing something ??
thank you
Lou Stillo

You're in luck. In August on Off-Road.com, we have a very detailed technical article on how to rebuild non-rebuildable silencers. The fact that itís a CR 250 means that you should not have a spark arrester in it. Instead it's just a muffler.  The core of the muffler may have to be tapped out, just like we did in the tech article.

 

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SUBJECT: HONDA FORK SWAP
building 1993 cr 250 and want to put newer forks' 02-06 cr forks would 97 triple clamp work or can you suggest what to use; and my be a newer shock? Thanks
David Bradshaw


There's no way you're going to fit the newer forks to the older 1993 CR 250. You could make the forks fit if you use the newer clamps and steering stem, but you may have to fabricate a spacer for the steering head. You can refer back to our project CRF 230 for details on how to complete a fork swap.

 

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SUBJECT: 1999 HONDA XR2 TO 50 MODIFICATIONS
Hello Rick,
Im glad to see The Super Hunky is back in action. Ive got a 99 XR250r,24,000 miles on it,(I added a speedo when I first bought it new,as part of my dual sport kit to get it plated) As per your article,Ive changed the oil every 600-700 miles,no exceptions,Im going to do a frame off resto to the bike,the engine paint has came off in spots due to washing it often,What would you do to this bike engine wise if it were your project?All it has so far is a FMF pipe,and FMF recommended jetting,uni filter airbox opened up,and 14/40 gearing,(All top end)All the free mods done as well.Also since your the best ever,What do you think about the Suz DR 650?I just bought a 06,with 103 miles showing on the clock.
Your the Man!! Thanks a lot.
SKEEFOO!!!

As long as you're going to do a good solid restoration to the bike, consider suspension mods. You could bolt a set of CR forks directly into the steering head of the XR without too much problem. All you have to do is be sure that the steering stem is the right length and itíll fall right into place. Then I would think about Works Performance shocks. Once you get good forks and a decent shock on this bike, it will really come alive. I've ridden XRs with real good suspension and found them to be a joy. As far as the DR 650 goes, it's very reliable bike with a great motor, but is very much on the heavy side. It will really benefit from taking a lot of heavy pieces off that bike.

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SUBJECT:  MORE YAMAHA VINTAGE DIRT BIKE GUIDE ID QUESTIONS
Really trying to find parts but don't know what year,or cc the bike is. The engine number is 2N6-003890. could you help please?! anything is helpful!!



Easy. You have a 1972 Yamaha DT2F, you lucky devil.

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SUBJECT:  EVEN MORE YAMAHA VINTAGE DIRT BIKE GUIDE ID QUESTIONS
I have a Yamaha CT1 018930
What year is this?
Brian

Here you go.  Much more than you needed to know.

CT1 Year: 1971 Start Engine#: CT1-000101
CT1B Year: 1970 Start Engine#: CT1-010101
CT1C Year: 1971 Start Engine#: CT1-200101/CT1-032101
CT2 Year: 1972 Start Engine#: CT1-065101
CT3 Year: 1973 Start Engine#: CT1-100101

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SUBJECT:  YES, EVEN MORE YAMAHA VINTAGE DIRT BIKE GUIDE ID QUESTIONS
i have a 1973 yamaha with serial number 465-002-073. need model number
Shannon Landry


Itís a 360 MX and is a keeper if itís in good shape.

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SUBJECT:  JETTING AND PORTING A RM125
what size jets do I need to use with a port and polished head with a o.o40 overbore on a suzuki rm125 cc dirtbike? I already have a45 pilot jet but Im not getting any bottom end power all my power is on top end so do i need to go up on my pilot jet or go down and what size?
Chris Jones


This may come as a surprise to you, but a stock 125 race bike doesn't have much low end for starters. And if you ported and polished it, you're going to lose the bottom end you did have and all the power is going to be on top. So I don't care if you put in every jet ever made, this bike is not going to have any low-end power. What you have to do is put in a fresh spark plug and do a high-speed run, chop the throttle and take a plug reading. If the plug looks lean, go larger on the main jet and do another run, followed by yet another run, followed by one last. When you get to a chocolate brown or tan color on the sparkplug, the jetting is correct.

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SUBJECT: CR 250 BACKFIRING PROBLEM SOLVED
happy happy happy,
Hi Rick,
Kirk Conway from Kansas,
I just saw the comment on the Out Of Control Yamaha,I was soo glad to see that all is not lost on this Honda CR 250R, E,. stuck float/ needle combo), Mine Is doing the same thing, then backfiring out the pipe, Rick, I was soo happy to know what Is going on, I couldnt figure it out? But Now I know,

I know what you said about the 85 CR 250 steering, But Is there anything I can do to firm It up? This thing Is a rocket Rick as you know, I just need to get it dialed In to enjoy It.
Thank's Alot Rick,
Kirk Conway


The needle/combo problem can hit most anybody. Glad to hear it's cured your CR 250 hassles. As far as making the CR steer better, just about the best thing you can do is raise the forks slightly in the triple clamps and pop a really good front tire on it, something like a Metzeler.


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SUBJECT: TWO-STROKE GAS-OIL RATIOS
thank you but what about a 2007 honda 450 cfr i dont have the manual because i bought it off a friend brand new but he couldnt ever find the manual so what do you recomend
Christopher Ryan Priddy



This may come as a shock to you, but the CRF 450 is a four-stroke and does not need any premixed gas in it. Who in their right mind said that it did? I think you ought to get a manual and spend several years reading it. However, based on what you just wrote me, it's possible that you don't know how to read and may have to have someone read the manual to you.


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SUBJECT: YET ANOTHER MISERABLE CHINESE RAT BIKE
I have a 2004 Panterra 125 Dirt Bike, working on the Carburetor. Has some kind of number on it like 20HSSDe. Looking for information on adjustments. Think I have the float set right, cleaned everything. Only one screw inside the bowl area that looks like it needs to be set right. Has a tiny pin point on the end of it and the hole comes out in the Carb. Throat. The Motor starts with starting Fluid. checked the gas line to the Carb. Then took the Carb. off . Cleaned it again. For some reason not getting fuel.
Thankyou
Gene Bridges



You don't have a dirt bike, Mr. Bridges, you have a cheap Chinese knockoff. I go out of my way not to have anything to do with these horrible rip-offs of real dirt bikes. Sorry, I sugarcoated it.

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SUBJECT: THE CHOKE IS THE CLUE WHAT RM 250 PROBLEMS
I have a Rm 250 bored over twice and when i rev it, it sticks unless i have the choke on partially. Idk what it is i have taken the carb off and cleaned it but it still do the same. I would hate to put it in the shop because of something stupid. can you tell me something.
Chris Dorsey

The fact that you must have the choke on a race bike to keep it from melting tells me you that you are running too lean. The pilot part of the circuit lends about 5% for carburetion to the bike. Add another 5% for the starting circuit and you can see that the bike is simply too lean. Take a plug reading to check the color of the spark plug and that should give you a hint as to what's happening.

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SUBJECT: CAN'T FIND THE CARB FOR A YZ 125
Hi there,
im looking for a carb for my yz 125 1992. but cant get anywhere, they are discontinued and so thot, can u help me with some info what other carb would fit and fork as good as orig???
thanks
Andris.


Considering the fact that 95% of the dirt bikes sold in this country come equipped with Mikuni or Keihin carbs, it doesn't take a brain surgeon to figure out how to get one. You could go to Mikuni America and get the carb ordered. Or you could even go on eBay and find whatever kind of carb you need. Youíre not even trying. Now go away.

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SUBJECT: A 1996 KX 80 IS JAMMED?
The kickstart on my 1996 kx80 is jammed and wont kick. i was riding it and it just bogged out and died. i kicked it several times but didnt start before it jammed. what do u think the problem is??????
Bree Anne Agee

I hate to be the one to bring this information to you, but your kick starter jamming is not the problem. The problem is more than likely that your piston stuck in the cylinder. When that happens, no matter how much you jump up and down on the starter, it won't move. It's time for you, or someone who knows what they're doing, to take the top end part and fix it.

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SUBJECT: A CHINESE BIKE PROBLEM OF SORTS
why does my bike start wide open., cant find out what it is.. any sugestions, its a baja 125 2007
Bob

 


Your bike starts wide open because it is a cheap Chinese ripoff of a real motorcycle. Quality control in these bikes is laughable. And the person who sold it to you is a real pinhead, which makes you even more of a pinhead because you bought the damn thing. Maybe, just maybe, this will be a learning experience for you. Get off of the Chinese knockoffs and get a real dirt bike and you wonít experience problems such as the one you've described.

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SUBJECT: 1980 HONDA XR250 GAS PROBLEM
HI RICK HAVE 1980 XR 250 WITH GAS RUNNING OUT OF BOTTOM OF FUEL BOWL LINE OR ANOTHER CARB THATS INTERCHANGE ABLE.
THANKS
Lino Larosa

First off, quit writing your e-mails in caps. That's considered foul manners. Now that we got that out of the way, chances are very high that the float needle is leaking in your carburetor. Take the float bowl off, remove the float needle and check it for wear.  It's possible that you have a little bit of debris in there causing the problem, but more than likely simply replacing the needle should solve your problem. I have no idea what the interchange carb garble that you wrote is all about.

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SUBJECT: OIL LEVEL AND A HONDA CRF 230
how much engine oil does my crf230f hold
thanks
Drew S
New albany, PA

I have a Honda CRF 230 and I also have an owner's manual, which tells me not only how much oil the bike holds but also told me what kind of oil to use. The manual recommends pro-Honda GN4 or HP4 without moly additives. It's a standard four stroke oil or you can use any oil with an APIs service classification of this or higher. 10w40 oil is what's called for. The oil capacity is 1.1 US quarts when it's drained, or 1.3 US  quarts when the bike is the disassembled.

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SUBJECT: FOR SWAP ON A HONDA CRF 230
I have installed a honda crf 250 /450 front forks on my crf230. you need to machine a new bearing stem/shaft to press into the honda PRO TAPER triple clamp so the lower clamp bolts will clear the tank, and to fit the 230 bearings, and a bushing to fit the upper clamp so the 230 stem will fit the upper clamp. I used the x front wheel so that i could have a speedo / odometer. the 250/450 bearings are bigger and about one inch further apart the reason for the new shaft. works awsome with 20 degree clamps in the mountains 6000 to 11,000 ft great air cooled trail bike no over heating
Brian Louw



Congratulations on using your head with real good modifications. Once you get a decent suspension on the CRF 230, it's one of the most pleasant trail bikes imaginable. Keep in touch with any future modifications that you might perform.

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SUBJECT: WHICH POWER MAX 200 IS IT?
I just bought a 2006 power max 200. iv e never heard of them before. it has a weird vibration during excelerating, and also does it when being reved up sitting still. ive checked all motor mounts, proper tire alignment and chain tention, what is your thoughts? thanks
Kevin


I did a search and found two versions of the Power Max 200. One is a bike and the other is a quad. Both of them are cheap Chinese ripoffs and don't deserve to be sold to people anywhere at anytime. I attached photos of both the bike and the quad mostly so other people can stay away from them. The vibration you mentioned could be caused by most anything, but more than likely it's caused by sloppy quality control when constructing.

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SUBJECT: 99 CR 125 BOGGING THROTTLE RESPONSE
I have a 99 CR 125 Honda and I can't get the Carb adjustment right it boggs real bad when I roll back on throttle if I ease it back it's fine what adjustment would u recommend please be as specific as possible as I don't know much bout Carb
John

John, you have to face the fact that you have a 125 motocross bike and it's not going to have a low end at all. You can adjust it until the moon turns into blue cheese, it's still not going to have the low-end. If you have a real problem with the bike responding, it's possible that you have some crud in your float bowl. Iíd check this first before I panicked.

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SUBJECT: THE ULTIMATE VINTAGE DIRT BIKE GUIDE
You say the Rickman 125 six day is very rare - I am restoring a 1974 six day. Do you know how many were made and why it's "very rare".
Thanks,
Terry

You've got to be more specific than that, as Rickman made a number of 125 packages specifically for Six Days use. No one has the actual numbers of the various bikes they made, but they are indeed limited in their number and quite sought after as collectors.

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DIRT BIKE MAGAZINE CD SET
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 to our STORE on
www.superhunky.com for details.

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