89 r mods

[ohiobanshee]

I just bought a 89 r. What are the more populay mods to do to these for trail riding? Going to have it trail ported,allready has a fmf fatty pipe and v2 reeds. eric

[dunatic]

Im posting this a reply from another thread. Some or all may not apply to you and your bike, but all are useful and work.

I have built (and rebuilt) over 30 "R" motors in the past 20 years.

Hands down, if your on a budget here are some simple things to do, that dont cost a ton of money and you can feel them in the seat of your pants and your wallet:

1. Bore to the next size with fresh piston, rings, bearings and seals throughout.

2. Shave the head .030-.035" and run the "CR" gasket.

3. Lighten the flywheel. Send it to Dave Moore Racing in Oregon, he can do it the usually the same day and have it right back out to you.

4. Install a Hinson/ModQuad/RPM counter balancer holder-timing advancer. Set timing to 3-3.5 degrees advanced. Set the stator to pick up gap and the new NGK BR8ES (resistor type makes more power) spark plug gap to .018".

5. Remove the spark plug boot from the coil wire. Cut approx 1/4" off and reinstall it.

6. Install a boysen RAD valve. CR type.

7. If you are running a Keihen carb (PJ, PWK or AirStryker)

a. Install a DEG or DEJ needle...in the 3rd position (middle).

b. 175-180 main jet

c. If over 180psi cranking compression, install a 50 pilot. If under 180 psi, install a 52 pilot.

d. turn the air screw out 1.5-1.75 turns.

8. Take compressed air (with the fuel tank 1/2 or more full) and blow back up thru the fuel tank petcock lightly to loosen any and all sediment that has collected around the screen. Remove tank shake well and dump everything out. You may need to do this a couple of times to get all the particles removed.

9. Remove the "inline" fuel filter (if you are running one) and replace the hose from the petcock to the carb.

10. Replace the clutch fibers with OEM factory plates. Take the steels and scratch both sides across 80 grit sand paper in various directions a lot. This will get you extra bite. Soak the new fibers in ATF (Type F) over night. Install new Toomey or Barnett springs and install (if not done already) the 88-89 clutch update from Honda.

11. Tranny fluid.

a. If you have lots of time on your hands to maintain you bike, then run cheap NAPA Type F automatic transmission fluid and change it after every ride. It runs $1-2 per quart and you only need a quart.

b. If you only plan to change it 1-2 times a year, then run a synthetic MTF (manual transmission fluid), like Torco or Redline. It runs $9-12 per quart.

12. Replace or clean and re-oil your air filter. If running the stock air box, remove the lid completely. Only if you submerged the air box will this be an issue.

13. Chain and Sprockets

a. If you like the gearing you have (such as 13-39 or 3:1 ratio). Install a 15 tooth front sprocket and a 45 tooth rear. Then replace your (probably $100+ high zuit oring bad boy) chain with the best non-oring chain you can find. I like the GP HD. 7250 lb tensile strength and their like $35-45 (so you can replace them 3x for the same price). By changing the gearing as such, you do a couple of different things.

First, youve added several teeth at are engaged to the chain at all times by going to more teeth. This causes less wear on the chain and sprockets by disbursing the load across more links and teeth.

Second, it requires a longer chain to reach around those bigger sprockets, thus you have more links that engage less per revolution.

Third, by doing so, you've decreased the load on the tranny, clutch and drive train, by increasing the load to more links and more teeth at the same time. Less shock and pull as the swing arm runs thru it's arc and the chain tightens and loosens.

Fourth, the resistance on all those orings causes drag. Running a non-oring chain will get more HP to the rear wheels. They do require more maintenance, but you should be oiling your chain after every ride and wash anyways.

[ohiobanshee]

Thanks What is a good size carb to run?

[dunatic]

38 or 39mm and the ESR TRX5 pipe

[k265r]

ride it see how you like it before you make any changes.

[pimpt250r]

what kind of performance gains will you have by advancing the timing that much 3-3.5 degrees

[dunatic]

by advancing the timing, you can add more fuel. the combo will give you the gains.

There is no crystal ball nor magic number. It's all in how you put your combo together.

All of the things that I spoke of above are nearly free and together it will make your machine run at it's highest efficiency.

[morse250r]

i picked up 7 hp on a cr ign advanceing it on a dyno yesterday

[pimpt250r]

but by advancing or retarding where would you see your gains in the lower, mid, upper end of the RPM and how signifigant would they be ,I know stock R motors are seriously detuned but what about 1 thats high compression and set up for low end would I notice any changes at 1 degree or do you have to make a big jump like 3 degrees

[dunatic]

there you go..........a real life testimony.

Others gains will vary....some might see none, but its easier to start both cold and hot.

[morse250r]

im told leaving it at this kick back maybe a consern but with that kind of gain ill take my chance

[dunatic]

thats why I suggested only 3-3.5 degrees advanced. You should have any problems.

[dunatic]

Originally posted by pimpt250r
but by advancing or retarding where would you see your gains in the lower, mid, upper end of the RPM and how signifigant would they be ,I know stock R motors are seriously detuned but what about 1 thats high compression and set up for low end would I notice any changes at 1 degree or do you have to make a big jump like 3 degrees

throttle response at the mid to upper rpms is where youd feel it most, since the jetting change that would take place would be on the main jet and needle.

you could start with 1 degree, but I dont think that it would be enough to warrant the jet change, thus you probably wouldnt notice any difference.

[ohiobanshee]

Thanks,Now I know what I have to buy.

[k265r]

have you went trail riding yet?

[ohiobanshee]

Not yet,bike is in pieces. Have to rebuild the motor.

[pimpt250r]

I was playing around today a little with the timing and right at about 2 degrees advanced the difference is DEFINITLY noticable and seems to be right where I want it,

I tried a few other settings but man what a difference 2degrees advanced made ,only wish I moved it sooner

the butt dyno recommends this mod :D

[All250R]

Originally posted by k265r
ride it see how you like it before you make any changes.

This is the best advice in this thread. You don't need to fall into the trap that because a part is advertised you should bolt it on. The stock engine has a lot of detuned characteristics to it as said, but a trail engine is not too different from what Honda built into the engine already. You can definitely pick up gains by adjusting certain characteristics of the engine, but you need to put the engine together and ride it before you spend your money.

The items you really do want to spend your money on, especially since its already disassembled are the maintenance items that it surely and maybe even desperately needs. You may need a crankshaft that will cost a couple hundred dollars. A new top end will run you a couple hundred as well. The gears need to be inspected. A new bearing and seal set is under $200 as well. If you don't take care of these items as your first priority whatever power increases you make are going to send the engine to its death that much faster, and that is more expensive than doing it now.

As far as performance mods are concerned, the advice given may or may not be for you. You do want to assemble a fresh engine and ride it first. The more you modify before you know the engine, the more difficult it will be if something is wrong or not to your liking.

Specifically milling the head AND putting a CR head gasket will raise your compression incredibly. This gives great low end power, but it reduces the maintenance interval on main and rod bearings and you will also have a recurring racing fuel bill that far exceeds the cost of pump gas. If you don't raise the octane in your fuel your top end will seize. The same goes for advancing the ignition timing. If you don't understand why you're advancing the timing at what other parts of the motor this effects, you shouldn't do it or should at least be aware and accept that you're walking in a little blind. Again, this not one size fits all advice.

A 39mm carb is not a trail carburetor for a stock bore cylinder. The 38 less so, but this is not carte blanche one size fits all advice. It's typically for people who like running higher rpm ranges. The TRX5 pipe is also a mid-high rpm pipe. These modifications will drop bottom end power and/or require large compression ratio's to compensate for if you find yourself dissappointed that you have to rev the motor to compensate for the lack of air/fuel velocity at low rpm.

The CR ignition provides no provision for lights. Do you trail ride at night? It also has an MX style flywheel that carries a lot less inertial energy. This nad cutting the stock flywheel are not typically a mod done for a trail bike. Maybe it's for you, maybe it's not. Again, this is not carte blanche advice - there are penalties for the gain.

Jetting. It doesn't matter what people want to think, jetting is not a one size fits all thing either, almost without variance. Ballpark jetting can be given with a disclaimer, but adding static compression value to the mix as well is very much wishful thinking. Same goes for plug range. A trail quad running at low speeds will try to shed a lot of heat through a small amount of air flow. A BR8 is a hotter plug than the generic BR9. Start safe and work your way hotter if you have a reason to. Not the other way around.

Once again, you really want to put the engine together carefully the way it sits hopefully with a stock ignition, do a compression reading to determine if you need race fuel and see how you like it and if it even runs reliably before you decide you need to change it.

p.s. Just my opinion, but I think the chain and sprockets advice is unnecessary.

[ohiobanshee]

I'm just trying to get some input on mods,what works and what doesn't. This is my first R. I have a 4mill strocker banshee ported by Jim Passion,a blaster with a CT Sonic cylinder,and a 10mill DM drag banshee.I know what works on the yamaha's but I don't have a clue about hondas. Thanks for all your help and input. eric

[All250R]

Originally posted by ohiobanshee
I'm just trying to get some input on mods,what works and what doesn't. This is my first R. I have a 4mill strocker banshee ported by Jim Passion,a blaster with a CT Sonic cylinder,and a 10mill DM drag banshee.I know what works on the yamaha's but I don't have a clue about hondas. Thanks for all your help and input. eric
It depends on how you want to ride it and your preference for maintenance and reliability.

[ohiobanshee]

Originally posted by All250R
It depends on how you want to ride it and your preference for maintenance and reliability. Woods, bike,bottom,mid portjob,need good throtle response,low speed luging,pump gas,reliable as a 4stroke.

[All250R]

Originally posted by ohiobanshee
Woods, bike,bottom,mid portjob,need good throtle response,low speed luging,pump gas,reliable as a 4stroke.
Cool! Man, what type of 4stroke... These days 4strokes have been shoe horned into the high output market, and they're not synonymous with reliability like they were when hp was a small bore 2stroke's job. I presume (and your builder) would presume you mean the more traditional 4stroke. Just to let you know, a 250R stock is a reliable machine for sure. However even a mild stock R has shorter maintenance intervals than a 400ex for example. The good news is lower rpm machines, unless the compression is cranked way up will require less maintenance than a dune engine with wide ports and peak hp at 9k rpm's for example.

My more specific advice would be assemble the engine with all the needful maintenance done and see how you like the setup without spending any extra money. Either have a builder do this for relatively small money or make sure you buy a manual or two (and maybe some special tools you don't own yet) set aside ample time, and take your time with it. Porting and doing the rest of the mods you may want shouldn't require undoing any of the maintenance money and time you spent and did aside from top end removal and gaskets...

Again, the stock setup isn't terribly far off from from your riding goals. When I bought my first R it was slightly modified and some of the small things like heavy duty clutch springs, handlebar position, shocks setup were beating the daylights out of me more or less on long rides and honestly it wasn't overly fun. It took me close to a year of trips to the dunes to get the chassis set up and me used to it so I could ride it closer to its potential with less energy. Only then did I start to get a sense for what minor tweaks I wanted done to the chassis and motor. If I'd spent the money and time before this learning period I surely would have made some changes I didn't need to or changed too much or too little of. The stock R is a lukewarm, but very fun bike. It's nimble like crazy (especially the 88-89) and the engine even with the stock pipe is easy, pretty revvy and has a decent hp level that provided you know where the rpm's start to fall off can keep you in a pretty fun zone of the motor. The point is an engine modification plan can only be made intelligently once you've learned the bike as it sits and a basic R with no or only minor mods is the best place to start.

[dunatic]

[i]
p.s. Just my opinion[/B]

yes it is, and everyone is entitled to one.

You sound like someone that has not spent the $100,000 that I have over the last 20 years riding, owning, building and modifying these "R"s.

You bring up some good points, but some of yours will gain you nothing and leave the owner wondering what it is that they did wrong and why they spent the money.

I agree that you need to start with a solid bottom end. One that is sealed tight and bearings are fresh.

You seem to have something against running race gas. Since most guys wont run thru but 5 gallons a day, and the difference between pump and race is no more than $3 per gallon, we are only talking about $15 at the most. the gains garnered by higher compression and a quicker revving motor are habit forming. The days of stump pulling are over. We all want to go fast, even in the woods when the needs allow. I dont know about you, but I have never had a motor tear up rod or crank bearings from running 190-200 psi of cranking compression. Thats all you will get from the head shaved and a CR head gasket if we are starting with a stock motor to begin with.

Unless you are running at 5000 ft elevation, the jetting SUGGESTION that I provided was only a baseline. Not a magic potion. Just a place to start.

A 38mm carb and a trx5 pipe are a good combo for that kinda setup. Im thinking that youve never owned either at the same time, otherwise youd swear by them together.

Im not trying to start a post war, but rather than tell the guy that he shouldnt try anything before he rides it and why not start with some basic upgrades or mods that will provide some serious effects.

Your speak of saving money (maintenance intervals/crank rebuild, rod bearing failure, etc.), but than you act like he is made of money. Build a stocker, ride it, then modify it.......we all dont have your wealth i guess.

the fatty pipe has the widest of all power bands. I did a 13 pipe test on a mule motor 6 years ago and it came out on top for power band.

He mentions "trail porting". I dont know what that means since he didnt include port height, width or port timing.....maybe your crystal ball is a lil clearer than mine. But to me that means higher compression and BIG - WIDE power band and near instant throttle response. Something a 36mm PJ will never do.

[05BlackYFZ]

Originally posted by dunatic
Im posting this a reply from another thread. Some or all may not apply to you and your bike, but all are useful and work.

...

13. Chain and Sprockets

a. If you like the gearing you have (such as 13-39 or 3:1 ratio). Install a 15 tooth front sprocket and a 45 tooth rear. Then replace your (probably $100+ high zuit oring bad boy) chain with the best non-oring chain you can find. I like the GP HD. 7250 lb tensile strength and their like $35-45 (so you can replace them 3x for the same price). By changing the gearing as such, you do a couple of different things.

First, youve added several teeth at are engaged to the chain at all times by going to more teeth. This causes less wear on the chain and sprockets by disbursing the load across more links and teeth.

Second, it requires a longer chain to reach around those bigger sprockets, thus you have more links that engage less per revolution.

Third, by doing so, you've decreased the load on the tranny, clutch and drive train, by increasing the load to more links and more teeth at the same time. Less shock and pull as the swing arm runs thru it's arc and the chain tightens and loosens.

Fourth, the resistance on all those orings causes drag. Running a non-oring chain will get more HP to the rear wheels. They do require more maintenance, but you should be oiling your chain after every ride and wash anyways.

Who makes a 45 tooth rear sprocket? Also, do you recommend aliminum or steel sprockets? Where can I find a GP HD non o-ring chain?

[dunatic]

Sprocket Specialties and sidewinder do.

Ironman go up to 43 tooth



I have (1) 130 link left, but any dealer that buys from Advantage Performance can get you one.

with the larger sprockets, aluminum works just fine and will last you years if you maintain your chain and obviously dont smack it on a rock....for that matter, a steel one wont last long either.


Originally posted by 05BlackYFZ
Who makes a 45 tooth rear sprocket? Also, do you recommend aliminum or steel sprockets? Where can I find a GP HD non o-ring chain?

[05BlackYFZ]

Originally posted by dunatic
Sprocket Specialties and sidewinder do.

Ironman go up to 43 tooth



I have (1) 130 link left, but any dealer that buys from Advantage Performance can get you one.

with the larger sprockets, aluminum works just fine and will last you years if you maintain your chain and obviously dont smack it on a rock....for that matter, a steel one wont last long either.

I'm still running the original 86' sprockets and chain so I need to update anyway. I'm thinking about going 14/42 and trying it out. I'm also going to pick up a 13 front for the tight dunes I ride, sometimes my gearing seems a little high there. How many links do I need to run that gearing combination on a stock length 86' swingarm? Will I need a shorter chain if I go down to a -1" swingarm, or can I just remove some links?

[dunatic]

120 link might be perfect, but Id hate to think you were 1 link short.

The difference in cost between 120-130 is $5

Ill ship you the one that I have for $45. It will come with two master links in case you change your swinger length, go bigger on the sprockets yet or by mistake cut it too short.

Not to mention, its nice to have a spare in the tool box just in case.

Id roll your carrier almost all the way forward, cut the chain for your new sprockets and install it. that way you can alway roll it tighter as the chain stretches or you go smaller

[05BlackYFZ]

Will a 42 or 45 tooth rear sprocket cause any issues with a skid plate?

[dunatic]

it might....how much room do you have now and what size sprocket are you running ?

Ill measure the diameter of a 42 for ya and let you know.

[05BlackYFZ]

Originally posted by dunatic
it might....how much room do you have now and what size sprocket are you running ?

Ill measure the diameter of a 42 for ya and let you know.

I'm not currently running a skid plate, but I sure would like to protect my new stuff when I get it. I'm doing a complete rear rebuild on my 86' project; new axle, anti-fade locknut, brake rotor, sprockets & chain, and possibly a new swingarm. I still haven't decided if I want to spend the money to go aftermarket or just cut my stocker down -1". Any suggestions?

[dunatic]

well one way to combat the clearance issue with the rear sprocket is to go to a taller (25+") rear tire. The added 2 inches average will help a bunch.

[brymillen]

lets say he has a cool head,can you shave those down?? dont they just use an o-ring? if so why would you need a headgasket, fyi im a plumber and have limited mechanical abilities....other than a water pump lol

[LONG-ROD]

some cool heads are o ring and some like my power head from Duncan are not. You ghang the dome for compression I run a 19 cc and run straight 110 fuel I am under 265 cc and runa pwk39 and It ripps!!