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Agravated with CRF88 (used to be 70)

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Man.... Iam pissed... I cant get this thing (Sons bike), to roll on properly..

BOG BOG BOG,,,,,, I have a 98 pilot, HTB 88cc kit and this damn 35 slow jet....

Cant find a #38 slow jet to save my life, on top of that, the 20mm carb that came with the kit, isnt even a keihin, its some chinese crap.....

The guy at HTB told me that jets from an XR75 would fit! Huh... 1983....

Besides when I did locate a parts sheet... they only make the #35 jet...

There is so much bog its almost no fun to ride.... She is a ripper mid to high..

I have the BBR exhaust. just a bog dog... HElp help help....

I am thinking of giving up and just getting the boy a KTM 65....Help me fix this thing... Do I get the inner rotor kit??? if so... which manual clutch kit...

Boy needs to learn the clutch. Please....... I am so agravated with this I cant think straight....

My son keeps asking is it fixed yet dad....

I am looking at building a mini 450x or 250x type bike....

or is my thinking all off.... I want the bike to rip down low and up top, but be smooth like my 450x.....

I am tired!!!!

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first off your mainje is way off go back to like an 87 jet there then try adjusting your needel and air fuel mix screw i usually start at about 2 turns out that should be a good starting point there

inner roter kit i love mine makes the tb kit rip down low

manuel clutch get the honda trail bikes kit

hopefully this will get u rolling

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Really???? WOW.... I will be try that, 87 huh??? I will tr anything at this point..

How smoothe does the HTB kit shift????

I am guessing that I should do these two mods together.....inner rotor and the clutch....

Correct...???

I will rejet tonight.... Fingers crossed....

Thanks Mano!!!!!!

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you dont have to put the clutch on for the inner roter my friends dont like clutches cuz they can ride and drink a beer but i dont think your son will be worried bout that the htb clutch shifts really nice i think the takegawa kit is a lil smoother but its what ever you want actually i run a 85main in my htb 88 race head w inner roter and clutch

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you dont have to put the clutch on for the inner roter my friends dont like clutches cuz they can ride and drink a beer but i dont think your son will be worried bout that the htb clutch shifts really nice i think the takegawa kit is a lil smoother but its what ever you want actually i run a 85main in my htb 88 race head w inner roter and clutch

o and if you want a inner roter i can give u a guys number that has one for sale for 175 plus shipping used twice by his kid

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Does the bike stall easier with the inner rotor and the stock clutch....

Can you get the rear wheel to spin with the inner rotor only and the stock clutch???

Thanks :thumbsup::ride:

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with the 88 i havent had any stalling probs

ps the guy w the roter kits number is 918-269-7875 ask for lance i was supposed to buy it but i found a cheaper on

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Ok... I started with the 87 main.... down from the 98.... Fuel screw two turns out.... Wow.... no more bog... well almost... But now... I get a poping when comming down from full throttle... That means lean....

right??? right!!! sooo I went to the 92 main... smae thing.... tried raising the needle to the clip clasest to the bottom.. so th needle sits the highest( rich) stil poping... Hmmmmmm

Is out on the fuel screw rich and in lean....???

I rember it being backwards on my CR250... I think cuz that was an air screw....

Help :thumbsup::ride:

Thanks

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I didn't change jets on my trailbikes kit at all. You just need a do some tiresome tuning with the air fuel mixture. Me and three of my friends all have trailbikes kit. I have installed them all.Built and overhauled all of them. One of my friends even has a BBR pipe just like you. The jets are the same ones that a Kitaco 20mm uses. Put the needle back to the middle and do some riding. Listen to the popping deep means too rich and high pitch snapping is too lean. Also get a new plug that can handle a higher heat range since you now have a 88cc too. Check the plug every soo often until you have the setting you want. Stick with it never give up. Semper fidelis

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What color is your plug now? If it is white then you are too lean. If the entire plug is white then you need to go up on the main for sure. You have to make sure you get the top end right b/4 you mess your transition from idle to WOT. After you get your plug to a nice brown color fine tune the idle then all you have to do is adjust your needle so you get a good transition w/o the bog.

And if the mixture screw is on the front of the carb then out is richer. If it is on the rear of the carb then out is leaner. I always remember front is fuel b/c they both begin w/ F.

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I had the same giant bog on my TB 88 when I built it and ended up running the stock carb until last weekend. I'd been exchanging emails with Ron at Xtreme Minis and he told me the Sheng Wey carb was a pile of dung, pointing his finger at the needle jet on the carb for causing the bog when I nail the throttle. I got to thinking about my "Woods Wing" XR-650L which ended up with a giant bog after I removed the snorkle from the top of the air box. It's needle was non-adjustable so I bought a nylon washer with a .110" I. D., 1/4" O. D. and .052" thick (cost=.09), sanded it on a surface plate to 1mm (.040"), installed it and no more bog!! I sez to myself, if it worked on the Big Dog will it work on the mini? Off to the hardware store, spend another .09, rush home and put the whole .052" washer under the needle clip after I carefully deburred it. NO MORE BOG!!! I still need to do some final tuning up or down on the needle but at least it's in a tunable range now.

Give it a shot!! It's as close as the local hardware store. :thumbsup:

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Your carb is jetted in fine for top end , if you can not get a bigger low speed jet(that is what it needs) just raise the needle all the way, its a good bandaid. I just played with a kids crf with the same kit last week with the same problem as yours.

When jetting in first get the top end feeling good then go back and fix the low end by the low speed jet, needle adjustment, and fuel/air screw. the main jet will not fix the low end bog!

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Thanks guys!!!! And Semper Fi right back!!!

Its definitely a low poping... Yes I remember now....what that high pitched lean poping sounds like...... I am relieved.... I willl check the plug tonight....

What high temp plug do you recommend???

Yea no 38 pilots available for this chinese piece if shit carb....

I am thinking of just biting the bulitt and buting a real keihin 20mike mike!!

Oh and I need a KTM 65sx...... ( I mean the boy does that is )

Thanks again!!!!

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As everyone has stated above, carb tuning is a definite trial-and-error process, and it sounds like you are close. Try doing a 1/4 in with the air screw (to richen it a hair) at a time, and then ride the bike. If it gets better, try another 1/4 turn in. It just takes time and patience to get it dialed in correctly.

All my bikes have 20mm Shengway carbs, and every one was a minimal amount of adjustment to get them dialed in. About the only way to get a Keihin pilot jet to fit is to have it turned down on a lathe, the Shengway pilot jet is a smaller diameter, and is seated right alongside the main jet aperture.

When the adjustment screw is located to the rear (or airbox side) of the carb, it is an air screw, and is turned in to richen the mixture. When the adjustment screw is located to the front of the carb (intake side, usually underneath center front), it is a fuel screw, and is turned out to richen the mixture.

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Thanks guys!!!! And Semper Fi right back!!!

Its definitely a low poping... Yes I remember now....what that high pitched lean poping sounds like...... I am relieved.... I willl check the plug tonight....

What high temp plug do you recommend???

Yea no 38 pilots available for this chinese piece if shit carb....

I am thinking of just biting the bulitt and buting a real keihin 20mike mike!!

Oh and I need a KTM 65sx...... ( I mean the boy does that is )

Thanks again!!!!

Well for the plug get hm..if the crhsa 6 is the normal one so go up to a crsha 8. If you are tired of the shing fe or what ever the carb is called . I will tell you a secret me and my friends discovered. Go to t-motorsports.com . They sell knock off parts up the ass,but! We found something in their pile of crap. Authentic Mikuni 22mm Carb for an steal! $59.99. You can't beat that price anywhere not even used period! After I just anounced this I don't know how much longer they will have this. Also go to minis to the max and go to the links and save it to your favorites. This has every companies link you will ever need.

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I just looked up what a Keihin PC20 costs at xr50.com Keihin PC20 Carburetor Kit CRF50 - XR50 & 70 Sale price: $186.99. A 22mm Keihin cost Keihin PD22 Carburetor CRF50 - XR50 & 70 Keihin PD22 Carburetor CRF50 - XR50 & 70. It comes with a intake and a throttle cable but when you buy the mukuni from t-motorsports.com you save $127.00! I do not have any affiliations with that site either I just want to help out every rider cause that is what this site is all about. Also I support the military.

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A CR8HSA is actually a colder plug, the CR7HSA is what everyone runs for optimum performance.

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Brand X Minis is offering 22mm Mikunis starting at $39.00 on eBay. I bought one at that price plus $9 shipping--what a deal!! Since I finally figured out my Sheng Wey I'll probably use it on motor #2.

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Just to clarify...

Roll on seems good... I get some deep poping if I rev the engine and let it come back down, haven't checked the plug yet.... Deep popping better than high pitched ........ Should there be a point wherer there isn't any poping at all??? When I ride the bike it seems fine.... when I rev her in neutral,,,, is when she pops... She pulls real well. with my 190 lbs on it.... my boy weighs 60 lbs. Should go real well with him on it.... I think i will see more of the 88 cc with the new pipe and the proper jetting.... Still no real snap.... but much more power... He will see snap with his KTM 65....

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If you still need the 38 pilot Jet, give Classic Honda a call. I bought a Keihin #38 pilot jet from them, shipped it was about 15 dollars and fit the Sheng Wey carb fine. It is part number P248

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