Don't Ask: Dirt Bike Tech Questions Answered (April)

Apr. 12, 2010 By Rick Sieman

If you choose to e-mail 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 … I’ll leave your e-mail unedited, for what it’s worth.

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SUBJECT:  TALLER HONDA CRF230F?

hey i have a 2003 honda crf230f and i was wondering to to raise the height on it with our buying new suspension or upgrades. is this possible/ if so how do i do it??
Jeremy
Toronto, CANADA

About the cheapest way you can raise the height of the bike is to add a few inches to the saddle.  Most any upholstery shop can do the job.  And it’s Mister Hey to you.

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SUBJECT:  LET YOUR FINGERS DO THE WALKING

 I have a 2001 rm 125 and the crankcase oil is leaking into the cranksfaft through the seal. I have the seal but need to now how to split the case?
RC Man
Payson, AZ

Why don’t you simply pick up a genuine workshop manual?  You’ll find them on eBay all over the place.  The option is for us to publish about 20 pages of how-to.

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 SUBJECT:  1982 YZ125 HARD STARTING

Question#1 my rear shock is spongy should i charge it with nitrogen and if so how much, oh ya its a 82 yz 125. Question #2the bike has compression but it is hard to start. if i put a tablespoon of fuel where the spark plug goes it starts right up was wondering if u could help me out with this. Question#3 my bike won't just sit and idle is this normal
Josh
Parma, ID



Take the bike to a dealer and have him check the Nitrogen level.  I believe your bike takes 200 p.s.i. Putting raw fuel in the barrel is asking for a bent rod.  Chances are you have a clogged pilot jet.  You can make the bike idle by adjusting the throttle cable.

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SUBJECT:  1998 KAWASAKI KX60 BOGGING BADLY

i have a 1998 kx 60 i bought for my daughter, it runs good with power, but when you rev it it boggs down and then catches and accelrates. it is also having problems idiling. any home maintenance i can do? also clutch is having problems, always hard to get into nueteral and taking off. have adjusted it a few times. time for new plates?
Jeff
Columbus, OH

Chances are that you have crud or water in your float bowl.  Clean it out and clean the jets as well.  Since the bike has considerable time on it, the clutch could be worn.  But before you spend any money, make sure the clutch is adjusted right and that the clutch plates don’t have badly worn tangs on them.

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PAGE 2

SUBJECT:  WHEN DOES THE SPARK HAPPEN?
hi rick,
i have a 2003 ds 650 bombardier im getting fire and gas but it wont run just back fire
Ray
Spotsylvania, VA

If all those things are right, then it’s a simple matter of timing.  Period.


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SUBJECT:  JETS FOR A YAMAHA TTR230 -ARTICLE TITLE: PROJECT YAMAHA TTR230 - PART 3 - DIRT BIKE BREATHING MODS

HEY I WOULD LIKE TO KNOW WERE TO GET THE JETS CANT FIND THEM ANY WERE AND THATS ALL I GOT TO MODIFI DID EVERY THING ELSE THANKS
CHRIS
Willcox, AZ



You’re not even trying.  Most any Yamaha shop should have the jets, or can order them.  And quit typing IN CAPS!

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SUBJECT:  TORQUE SPECS FOR JUST ABOUT ANYTHING

what do i torque the head and jug bolts at for a 1989 kx 80 thanks
Bubby
Kittanning, PA

Here you go:
(C) = Coarse thread, (F) = Fine thread



Hardness

Grade 3

Grade 5

Grade 8

Stainless Steel /
Special Alloy

Bolt Size
 

No lines = Grade 3 bolt

3 lines = Grade 5 bolt

6 lines = Grade 8 bolt

Stainless Steel / Special Alloy bolts

1/4-20(C)
1/4-28 (F)

70 in. lb./ 6 ft. lb.

115 in. lb./10 ft. lb.

165 in. lb./14 ft. lb.

14 ft. lb.
 17 ft. lb.

5/1618(C)
5/1624(F)

85 in. lb./ 7 ft. lb.

140 in. lb./12 ft. lb.

200 in. lb./17 ft. lb.

29 ft. lb.
 35 ft. lb.

3/8-16(C)
3/8-24 (F)

150 in. lb./13 ft. lb.

250 in. lb./21 ft. lb.

350 in. lb./29 ft. lb.

58 ft. lb.
 69 ft. lb.

7/1614(C)
7/1620(F)

165 in. lb./14 ft. lb.

270 in. lb./23 ft. lb.

30 ft. lb.
 50 ft. lb.

98 ft. lb.
110 ft. lb.

1/2-13(C)
1/2-20 (F)

260 in. lb./22 ft. lb.

35 ft. lb.
 40 ft. lb.

60 ft. lb.
 80 ft. lb.

145 ft. lb.
160 ft. lb

9/1612(C)
9/1618(F)

300 in. lb./25 ft. lb.

55 ft. lb.
 75 ft. lb.

105 ft. lb.
115 ft. lb.

200 ft. lb.
220 ft. lb.

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 SUBJECT:  THE MYSTERIOUS HONDA XR200 CONNECTION

i have 83 XR200 that I took outside today. we were riding for about an hour and then my nephew dropped the bike on the right side. since then i cant start the bike. i checked throttle linkage, put it a new spark plug, carburetor, jets etc. and bike just wont start. did i miss anything?

Peter
Grand Junction, CO

Yep, check all the wiring connections.  In a fall, wires can get pulled loose easily.

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SUBJECT:  NUMBERS ON DIRT BIKES
 I was wondering which dirt bike numbers have already been taken, also how to get my own dirt bike number?
Thanks,
Karen
Seminole, FL

If you’re talking about the numbers on your number plates, they only matter if you’re racing.  When you sign up with a club or group, they assign you a number which you have to put on the bike in order to race. If, at the end of the year, you should win your class, then you can carry the Number One on your plates. 
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PAGE 3

SUBJECT:  KTM 125 MAXIMUM PERFORMANCE
i have a 1999 ktm 125sx it bogs down at high rpms and dont have the zippyness like it should and i was also wondering what a good way would be to get some more power out of it
Bobby
Fredonia. KS
Make sure the top end is fresh, jetting is correct and put some Boyesen reeds in.  That should do it.
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SUBJECT:  MAICO MUST DO THINGS
Hi Rick.
My name is Jeff Osborn.  I race in the Pacific NW...Hammer &
Tongs.  I am the proud owner of 2 Maicos.  A 1981 MC490 and a 1974.5
440 GP.  I just recently acquired these bikes.  I`ve heard a few Maico
guys say the same thing you said that they require close attention to
maintain their effectiveness.  What I am interested in is sort of a
list of the major points on a Maico that need the real attention.
Wouild you be so kind?  Thanks very much.

Take Care,
Jeff

There are a few things you should keep and eye on.  They are:  don't let the primary chain get loose.  Keep the rear sprocket bolts tight.  Same with the motor mount bolts.  The air boots tend to split or rot.  Base bolts on the bigger bikes need regular attention.  Make sure the head steady is firmly attached.  That's about it.

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SUBJECT:  READING MONKEY BUTT CAN GET YOU IN TROUBLE
READ ``MONKEYBUTT`` A FEW YRS AGO,NEEDS TO BE A MOVIE,!!!SAT ON THE BEACH AT PRIEST LAKE IDAHO LAUGHING MY ASS OFF. PEOPLE AROUND ME THOUGHT I WAS NUTS TILL I READ EXCERPTS OUT LOUD TO THEM!!
THANKS,
MIKE

Hell, you should have been around when I was writing it.
 
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SUBJECT:  WHO’S IN THE LEAD?
Hey, Rick, it's me again. I was checking out your "Super Hunky" page that looks like the old Dirt Bike Mag. cover and had a few questions: Where is/was the picture taken? When? Who has the massive lead? (#27)  I'm gonna guess on the location: Carlsbad?  Rider: Roger DeCoster? How many points do I get if I am right? Also, I have a fork assembly with wheel/tire I want to post on parts ad but can't finger out how to bring it up (I know, that's what she said) It is a Taco 99 fork w/suspension and origional wheel/tire that I want to give away. Nothing special (obviously) but I'm tired of tripping over it in my garage. I put one of those Chinese mini-crotch-rocket fork assembly w/mechanical disc brake on the 'ol Taco and it looks cool. Wow! Front brakes! Has rear brakes (internal expanding) but never hooked it up. Needs mods.  
Dave Fruhling


The photo was taken at Saddleback Park in 73 and the big lead is by Ake Jonnson on a Maico.  You certainly should have known.

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SUBJECT:  THE JUMP THAT WENT HORRIBLY WRONG
Super Hunky! You rule! The first From the Saddle I ever had the privilege to read was an account of how you cased a “gorge” jump at the L.A. Coliseum supercross. It was complete with an illustration of the bikes trajectory and impact point. Can you tell me what year/month this was published in? If I remember correctly, you stated that you were writing the article in bed with a typewriter across your chest due to the injuries you sustained in the crash. Thanks for all the great writing over the years.
G.H. Roach

The issue was October 1979, and yes, I typed with an IBM Selectric across my chest.  By the way, I also bench pressed 335 pounds while recovering.
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PAGE 4

SUBJECT:  KTM TOLERANCES
I’m rebuilding a 87 KTM 600 lc4 engine and had to use a crank from a 620 which is supposed to be the same.  I’m putting on the head and noticed that with a very thin head gasket from EBay, the piston hits the head and won’t completely revolve.  With the correct head gasket it doesn’t hit.  Is this too close of tolerance?  If so, could I increase the thickness of the base gasket to compensate?
As always, thanks for your help and sharing your talents with the masses.
David

Use only the factory gasket, period.  You could increase the base gasket thickness, but that would lower the compression.

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SUBJECT:  SUZUKI RM250 LOCKED UP
I have a 03' RM 250 2stroke, and It has ran strong until today. It died on me and when I went to start it, it just locked up. What is the most possible reason for this. The kickstarter is locked up. The bike recently had new top end and all fluids changed.
Snackwell22
Pearland, TX


More than likely, your top is stuck.  Chances are the piston/rings froze in the cylinder.  Take the top end off and check.

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SUBJECT:  NERVOUS BIKES  VS HANDLERS
Hi Rick,
hows it going? I hope good, Welll I got this CR 250 to the point of riding it, but then its fouling plugs everytime I try to start it, Ive been doing what you said about these bikes, they are squirelly and the power comes on wayyy too fast and hard, Ill take your advice and get a 73 Maico 400, OR A 73 CZ 380 AND BE AHEAD OF THE GAME, No more teetering on this Honda and knifing in turn's,
Kirk C.
Alton, KS

While the Hondas were fast, there was a reason the Euro bikes beat them.  There’s something to be said for predictable handling and proper power.

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SUBJECT:  YZ85 BOGGING REALLY, REALLY BAD

Hey Rick,
Ah I have a 2006 yz85 and it has run fine up till today. I have tried everything to fix it and I still can't find the problem. I can start it fine and go through 1st and 2nd gear fine and then hit the powerband in 3rd and shift into 4th, 5th, and 6th gear it bogs down really bad. I've changed the plug, cleaned the exhaust, put a new air filter on, and mixed new gas for it and it still isn't running like it should. Comment back.
Thanks,
Daniel
West Augusta. VA

Chances are very high that you have some sort of crud in your carb.  If the bike was running OK, then for no apparent reason it started running poor (mechanical failure aside), you have something blocking the fuel flow.  Take that carb apart and check the float bowl for some sort of debris, like water or dirt.  Under a load, this stuff gets sucked up into the main jet and the bike bogs, just like you described.

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SUBJECT:  STRANGLED CALIFORNIA BIKE LAWS

HI Rick,
Im trying to sell a 2003 xr650L. we had a guy come out from washington to but it but he turned it down because it was bought new in california. is there that much of a difference between a bike from california or washington? im just wondering if he was nuts ,or if we should put that on the advertising? i appreciate your time!
Nick
Lewiston, ID

California “L” models had a fixed pilot jet that could not be adjusted.  Consequently, the bike was too lean on the low end and hesitated badly when the throttle was rolled on.  The problem could be fixed by drilling out the fixed jet and tapping the hole for a regular pilot jet.  It’s not that difficult to fix, so you might do it yourself and mention in your ad that the fix has been done.
                                                            *** 

PAGE 5

SUBJECT:  GRAPHICS FIRST?   

Hey Rick.
This might sound like a stupid question and all but i just started riding dirtbikes last spring. So i'm not all that smart about bikes. Anyway, I have a 2001 KTM 125 SX that i traded a 2006 crf 230f for. he told me it was an 03 but its clearly not. it has alot of aftermarket stuff on it. although it has K-style graphic kits on it. I cannot find them anywhere on the internet let alone the local shops. Can you please give some insight on where to get or look for the K-style graphic kit? im in need of new plastic so i need the same graphics to match the seat.. thanks for your time.
Dyanearls
Ewing, KY

If you pick up most any dirt bike magazine, you’ll tons of ads for sticker kits of every possible bike or style.  A word of advice:  since you’re new at this sport, save your money for maintenance items instead of fluff like stickers.  Scrape all that crap off your bike and go for a clean look … and save some money in the process.

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SUBJECT: PROJECT YAMAHA TTR230 - PART 5 - DIRT BIKE JUNK FORK
In the article about rebuilding/resealing the newly installed front forks, you state they are from an '03 YZ125, in this article they are from an '03 YZ250, and in the project comparison article they are from a YZF250...and finally in the Project Comparison Readers' Questions article they are back to being from a YZ125! So, *exactly* which front fork/triple tree did you use?!?!?!?!?
Joseph
House Springs, O

Actually, the 125 and 250 forks are the same, with the only difference being the fork spring rate.
                                                            ***

SUBJECT:  HONDA CRF230 BACKFIRING PROBLEM
On my CRF 230 i have a BBR exhaust pipe but it keeps back firing when i let off the accelerator. Also the acceleration is slower. i think that it might need bigger jets but im not quite sure. Wat do You think?
Clint
Mt. Vernon, IN

Unless you installed the “power up” jetting kit we described in detail in the Project Bike series, you’re running way too lean, which would cause the backfiring you described.  

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SUBJECT:  FIXING YAMAHA SHIFTER SHAFT SPLINES

Hi
i have a 1989 yz 250 and the splines on the shifter shaft are stripped. how do i remove the shifter shaft?
Tyler
Columbus, OH

Believe it or not, I put some JB weld epoxy on a stripped shaft once and it worked for half a year.  If you want to do it right, then
get a manual and read it.  Yes, in there you’ll find instructions on actually how to do it.

                                                            ***

SUBJECT:  YET ANOTHER CHEAP CHINESE BIKE QUESTION
We just got an 03 50cc 4stroke Sidewinder by sunbird dirt bike for our boys, and want to change the oil, but can not figure out what the oil capacity is on it. the engine says china Liming IE40F and then a (star) 05136
Lanine07
DePere, WI

You just bought one of those pathetic cheap Chinese bikes and they never even gave you a manual with it.  As far as I’m concerned, you ought to pour cement in the oil hole.

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SUBJECT:  WAYWARD HONDA CR250 SPARK
hi i have a honda cr250 2005 it run fine then i went out on it once and after about an hour it cut out,i thought it was the plug fouling so i changed the crank shaft seals and next time it did the same so i did a top end rebuild and it still did it after that too.iv tride changing the jets to.if you put a new plug in it after it cuts out it fire s up and goes again.do you have any ideas i could try next.
Phil
Kent, ENGLAND

More than likely, you have an ignition problem.  The clue is when the engine gets hot, the problem starts.  Have a shop do a bench check on the electrics.

                                                            ***
SHAMELESS PLUGS:
BLACKWATER 100
Welcome to a celebration of The Toughest Race In America, the notorious Blackwater 100. Held every year in Davis, West Virginia, the race was designed by Dave Coombs to be a real test of survival. While the race is no more, the tales of this legendary race seem to grow with each passing year.
What we have here, is a collection of hundreds photos, stories and copies of some of the actual programs.  These images tell you more about the nature of the grueling course than the many tales that circulate.
Included in this great collection are stories about the race by Rick Sieman, who competed in this event numerous times.  You’ll also find a story and test on the legendary 760 Maico, the first bike ridden by Rick in the Blackwater race.
The Blackwater 100 is a two CD set.  On Disc 1, you’ll experience a slide show with some classic bluegrass country music to accompany the images.  Just put the disc in your computer, go to MY COMPUTER and hit the BLACKWATER 100 button on your  screen.  Make sure you turn your sound on for Disc 1.
On Disc 2, you’ll find the same images, but these are in Picassa 3 format and literally hundreds of photos are there. This means that you can stop any image, or copy what’s on the screen, make it bigger (or smaller) and print out anything you see.  Just go to the bottom of the screen and a very simple menu is there. 

Cost for the CD set is $20 plus $5 for Priority Rush mail.  Paypal, checks or money orders OK.  Paypal address is: [email protected].

Mailing address:
Rick Sieman
36607 W. Costa Blanca Dr.
Maricopa, AZ
85138
Go to http://www.superhunky.com/ for more info on other products, including posters, CDs and the Monkey Butt book 
Email: mailto:[email protected]


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