djhasin

Member
Sep 6, 2009
2
0
i have a 110cc pit bike not sure of the make or year bt i know it is made in china. the bike has 4 gears, 1 down and 3 up, the prolem is that when you pull the clutch and put it in 1st gear the bike jearks so i have to rev it and then put the bike in gear, the gear changes without pressing the clutch and sometimes when i change the gear own it goes into neutral it self, can anyone tell me what the problem is please.
 

Patman

Pantless Wonder
LIFETIME SPONSOR
Dec 26, 1999
19,774
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My guess is you have 2 problems and both are because of poor build quality and abuse. Depending on where on the quality scale your bike falls it could have been just riding it that could be abuse (yes some are THAT poor!) or it could be a middle quality engine that has just seen it's share or being ridden hard. Either way it seems you have a vlutch issue with the starting out issue you have and then a star gear issue with the shifting down problem. The star gear was a pretty common issue a few years ago but seems to have been sorted out for the most part. You will have to dig around in the depths of Google to find parts & gaskets to fix this issue because not every manufacturer was exactly the same. The slutch could be a simple adjustment issue or something more involved you won't know until you try afjusting the cable. In all honesty it's a better idea to just replace the cheap engine in your bike with another cheap engine from Ebay or another source. They were pretty much designed to be disposible except for the higher end bikes which were pretty easy to sort from the average China bike.
 

TheJunkMan

Member
Jul 9, 2003
586
0
As Patman stated there are a few reasons for the condition you are experiencing. It would be nice to have a picture of the engine (clutch side) and I could help provide some possible solutions.

First adjust the clutch properly. This will vary depending on what type of clutch you have. There are 3 basic styles Semi-Auto, Crank mounted clutch, and primary/transmission mounted clutch. If you don't know how to adjust the clutch I can type out a detailed procedure. This will cure the first problem with the lurching when shifting from neutral into 1st gear.

The second problem can be exacerbated by not correcting the first problem.
There are two fairly easy and inexpensive "fixes" you can try, but these involve removing the clutch cover and a few components.

First the most inexpensive fix (costing less than $5 and your labor) is replacing the shift star detent arm spring. Its fairly common (it became the problem on 2 different motors I have had) that the "stock" spring looses its temper or is weak and does not fully allow the detent arm to fully engage the shift star, thus allowing it to turn and change gears at will. The spring is available from any Honda dealer or distributor of OEM Honda parts. Below are some pictures for reference and part number.

Spring P/N the Honda spring is stiffer
http://i33.photobucket.com/albums/d80/princevaliant/10-20-07_1255.jpg

Crank mounted clutch type motor
http://i33.photobucket.com/albums/d80/princevaliant/IMG_3404-1.jpg

Transmission/primary mounted clutch type motor
http://i33.photobucket.com/albums/d80/princevaliant/10-27-07_1657.jpg
(clutch removed for clarity of the shift star and detent arm)
http://i33.photobucket.com/albums/d80/princevaliant/GPXside.jpg

The next thing to do/try is modify your existing shift star by grinding down the valleys and making the peaks more steep, thus a more positive engagement of the deten arm. The other solution along the same lines is replace it with a corresponding OEM Honda part. This is where some trial and error will come into play as you will have to order a shift star from several models to find what style they used since Honda changed the design ever so slightly from model to model on their horizontal engines. Try models like: TRX90, CT/XL/SL70, CT90/110.

If all that fails to fix the problem then the problem lies within the (worn) shift drum or forks, they are replaceable with the corresponding Honda parts, but in most cases it is just easier to buy a (known quality, Lifan, Jialing, GPX, Zongshen) crate engine and drop that in, such as these.

http://tboltusa.com/store/index.php?cPath=114

or these.

http://www.sgr-usa.com/index.php?cPath=153&osCsid=f68b39d5add5f5b66b43fe78f698467d

As well as other sources. However the two sources I list are reputable and will give tech support and or limited warranties.
 
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djhasin

Member
Sep 6, 2009
2
0
Patman & thejunkman you have been a really good help and i will reply soon with good news hopefully, but the clutch lever pulls fully because i have tightend the lever, i think i am going to have show it to a mechanic, cheers for the help fellas
 


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