Review of Kawasaki KX 125 - a motocross bike for beginners

Cheset 350: technical characteristics

The main power plant is a two-stroke engine with 2 cylinders. The cylinder arrangement is in-line. The working volume is 343 cc. At the same time, the motor is capable of producing 22 hp. The Port control function was used as a distribution system. The engine receives the necessary cooling due to the oncoming air flow.

The transmission consists of 4 gears. The main transmission is a metal chain. Drum brakes are installed at the front and rear of the motorcycle. Front and rear wheel sizes respectively: 3.25-18 and 3.50-18. The fuel tank is designed for 18 liters of fuel. The motorcycle is capable of reaching a maximum speed of 125 km/h.

Transmission

A multi-day motorcycle needs a higher maximum speed than a motocross bike and a slightly different distribution of torque among gears. Therefore, it is necessary to change the gear ratio of the motor transmission, gearbox and final drive.

Rice. 1. Motor transmission gears : a - driven (56 teeth); b - drive (20 teeth) and fourth gear: c - driven (15 teeth, pitch circle diameter 37.5 mm); g - drive (22 teeth, pitch circle diameter 55 mm). Module M-2.5; the original contour according to GOST 13755 is 68, its displacement coefficient is +0.8. Material - steel 12ХНЗА, cement to a depth of 0.4 - 0.6 mm, heat until hardness HKS = 54 -56.

We produce gears with 56 and 20 teeth according to Fig. 1. They will replace the 53 and 23 tooth gears of the motor transmission. The most suitable material is 12ХНЗА steel. In the box, to change the gear ratio of the second and third gears, we use two pairs of standard gears (17 and 20 teeth) for the third gear, and for the fourth we make new gears (see Fig. 1). We assemble the box as shown in Fig. 2. Since the order of gear engagement becomes different, we make a new selector plate according to Fig. 3. After assembling the box, we use washers to adjust the depth of connection of the side cams of the gears and achieve precise gear engagement.

Rice. 2. Layout of gears in the gearbox: 1 - input shaft; 2 — first gear gears; 3 — second gear gears; 4 - third gear gears; 5- - fourth gear gears. The numbers on the gears indicate the number of teeth.

To increase speed when driving on the highway, it is advisable to replace the main (rear) gear sprocket, which has 60 teeth, with a new one - with 53 or 55 teeth.

Rice. 3. Gear selector plate. Material - 12KhNZA steel, cemented to a depth of 0.4-0.6 mm, hardened to hardness HKS = 55 -58.

ChZ keeps pace

In recent years, competition in motocross competitions has intensified, especially in the 250 cc class. Today, a good two dozen companies in different countries produce such motorcycles for club racers. The technical performance of the cars has become much closer, and designers have to update sports cars almost every year.

For 1979, the Czechoslovakian CZ plant included an improved model CZ 977.3 in its production program. Changes compared to the well-known ChZ-980 car affected the exhaust system, front and rear forks, the location of the spokes in the wheels, the chain tensioner, and the front wheel brake.

Electrical equipment

The standard ignition system with two simultaneously operating high voltage circuits has proven its worth in multi-day competitions. The source that powers the ignition and lighting circuits remains the alternating current generator (6 V, 60 W). By increasing the gear ratio of the motor transmission, reliable engine starting from the kick starter is ensured. A headlight with a diameter of at least 100 mm with low and high beam lamps is used from any motorcycle or moped.

The brake light switch, borrowed from road motorcycles, is mounted on the back of the right-hand bib and is connected by a spring to the footbrake lever.

We take power for the lighting circuits from the low voltage contact of one of the ignition coils.

What is the maximum speed of the CZ-250

All sorts of topics related to socialist camp motorcycles

Moderator: Neposeda

ZaURALets Messages: 1327 Registered: 11/15/2009 From: Dnepr #46 Post by ZaURALets » Mon Feb 14, 2011 1:44 pm

For CZ-250/513 . Cluster frequency at Ne max-7800 rpm Motor transmission-21/55 4th front-19/18 Before chain-14/58 Rad. quality wheels-0.34m We get kinematics. speed Vmax=97.3 km/h . With a star at 15 Vmax=104.2 km/h Cz-380/514 At n=6800 and 14/52 Vmax=120 km/h

vitaharu Posts: 89 Registered: 09/07/2010 From: Kramatorsk #47 Post by vitaharu » Mon Feb 14, 2011 8:46 pm

Well, it finally looks like the truth!!!!!

ZaURALets

vova63

Messages: 603 Registered: 11/28/2010 From: Uman

#48 Post by vova63 » Mon Feb 14, 2011 9:06 pm
Destroyer

Destroyer wrote: vova63 , 400ku.
And this is not the end... There is something to strive for)))

I had no doubt about the engine...

I mean to keep this good on the road at such

speed..160 he goes to half throttle..what to do next

like this moto design

moto

kiryukha

Messages: 3316 Registered: 11/09/2009 From: Ukraine, Krivoy Rog

#49 Post by Kiryukha » Mon Feb 14, 2011 9:26 pm

what to do!

pray blah!

You can say the word halva a thousand times, but it won’t make it any sweeter in your mouth...

Avtokor

Messages: 1602 Registered: 05/06/2010 From: Sumy region

#50 Post by Avtokor » Mon Feb 14, 2011 9:29 pm

since the user Destroyer was banned, he asked to transfer)

vitaharu , but on the graphs is the speed not so high?))) vova63 , the chassis has been rebuilt, all the bearings are new. I also plan to get new shock absorbers.

vova63

Messages: 603 Registered: 11/28/2010 From: Uman

#51 Post by vova63 » Mon Feb 14, 2011 9:44 pm

but the fact of the matter is that, believe me, I also worked on everything on the chassis down to the smallest detail...165 and it blows like an aspen leaf in the wind. opticator... in my opinion this is the only option... I don’t see any more options... or make the motsyk heavier...

moto

maxbel

Messages: 241 Registered: 08/26/2010 From: Lugansk

#52 Post by maxbel » Tue Feb 15, 2011 12:15 am

Guys, if we wouldn’t play along, it’s clear that 150 won’t go, I probably drove a maximum of 75 kilometers on my Cheze. This is generally a stupid question “WHAT IS THE MAXIMUM SPEED OF THE CHZ” everyone understands that depending on what goals you set, what do you need speed or explosive dynamics? And this all depends on the selection of gear ratios of the stars (driven, driven and motor), as well as the number of gears, and the type of tires.

kiryukha

Messages: 3316 Registered: 11/09/2009 From: Ukraine, Krivoy Rog

#53 Post by kiryukha » Tue Feb 15, 2011 12:45 am

but here we were talking about the standard ratio of stars!

You can say the word halva a thousand times, but it won’t make it any sweeter in your mouth...

vova63

Messages: 603 Registered: 11/28/2010 From: Uman

#54 Post by vova63 » Tue Feb 15, 2011 1:38 am

well, if we are talking only about the chz-cross 250, then it’s well tuned

110 will work... but not for long

will jam anyway

moto

leonmotoblock

Messages: 716 Registered: 04/13/2010

#55 Post by leonmotoblock » Mon Mar 14, 2011 1:23 pm

But if you attach a sports pipe to the resonator and change all the stars to road ones and lower the suspension to reduce the ground clearance, then it will work?

0678873819,0636226446

RM-Z 450 '11 RM-Z 450 '06 ZX-10R '06

Destroyer

Messages: 992 Registered: 07/18/2010 From: Ivano-Frankivsk

#56 Post by Destroyer » Mon Mar 14, 2011 2:29 pm

What will a pipe from a sport to a resonator give you? The engine won't work there if you replace it with road sprockets. I already counted.

Spoke wheels: manufacturing, alignment. Boosting and tuning of 2T engines. Computer embroidery. Tuning electronic ignition, FUOZ.

leonmotoblock

Messages: 716 Registered: 04/13/2010

#57 Post by leonmotoblock » Mon Mar 14, 2011 2:52 pm

I was thinking about pushing down the power in order to draw out the resource so that it wouldn’t work...

0678873819,0636226446

RM-Z 450 '11 RM-Z 450 '06 ZX-10R '06

Destroyer

Messages: 992 Registered: 07/18/2010 From: Ivano-Frankivsk

#58 Post by Destroyer » Mon Mar 14, 2011 6:58 pm

Then it won't last any more.

Spoke wheels: manufacturing, alignment. Boosting and tuning of 2T engines. Computer embroidery. Tuning electronic ignition, FUOZ.

leonmotoblock

Messages: 716 Registered: 04/13/2010

#59 Post by leonmotoblock » Mon Mar 14, 2011 9:15 pm

It’s strange I saw on the net a Java 638 with a 981 engine under a cafe racer with a small star in the rear and a large one in front and a slightly muffled lower resonator of the old model. I really liked it, there’s even a video on YouTube of how it works

0678873819,0636226446

RM-Z 450 '11 RM-Z 450 '06 ZX-10R '06

Destroyer

Messages: 992 Registered: 07/18/2010 From: Ivano-Frankivsk

#60 Post by Destroyer » Mon Mar 14, 2011 10:48 pm

Let's take a look at the link. I'm not saying that it won't go. But I say that it won’t go more than 120)

Spoke wheels: manufacturing, alignment. Boosting and tuning of 2T engines. Computer embroidery. Tuning electronic ignition, FUOZ.

Let's start with the fact that my brain was enslaved by the idea of endurism, but in principle I’m not ready to change a road motorcycle to a “dirt” one (in my understanding, enduro is exactly what it should be), and the family budget is not quite ready to buy an enduro for >100 thousand, as well as contain both. and it’s not a fact that I’ll need it after the first trip))) Anyway, one day I was mulling through an ad, I came across a sale of a CZ-513 (with a 250cc engine) for a very budget price, but with a completely dead engine (to replace the crankshaft, CPG, clutch) which had been standing in the barn for about 10 years. The thought flashed through my mind - shouldn’t I try it... An hour later, with a fellow teammate in his 4k we were driving 150 km to pick up a motorcycle... In this form I saw him for the first time

visually it was in an obscene state, to put it mildly, the engine cranked with a crunch, there was no compression... but for such a price tag I was of little interest! For me, only the chassis in it was valuable...

the motorcycle was brought home

the engine was removed, the prices for spare parts made the hairs on end stand on end not only on the head... the Japanese are cheaper to repair, and after studying more detailed information, it was decided to abandon this engine altogether, because... its service life is 12-15 hours, which did not satisfy me at all

The motor was lying around in the garage, then in the spring it was donated to the guys from the motocross section... I think it is more needed than for me the motorcycle was completely disassembled. washed The suspensions were rebuilt, and the search began for an engine suitable specifically for enduro (high-torque, reliable)... and most importantly, inexpensive and unpretentious... Initially, there was an option for the IZH PS engine... but within Siberia it is extremely difficult to find one. so the motor was found. or rather, several from IZH Planet of various modifications, one was literally dug out of the ground behind the garage of the owner of this miracle... a small problem was that the Planet engine was 7 cm longer than the original engine... but I still managed to put it into the frame without violating its integrity

it was already autumn, there was absolutely no time to work on the motorcycle, everything was put on the back burner... around February, remembering that the motorcycle season was coming, active work began on weekends... The engine was fixed, the exhaust was welded - just from pipes, I started working on the resonators now , in order to regain the lost power... it was made from pipes, so as not to miss the mud season...

Time passed and then it came to the first launch... temporary wiring was installed. just to start the engine

started up and worked quite well... in the process of manufacturing this miracle, the engine acquired different positions... it was even like that

Then the box was glued together from epoxy and fiberglass, and installed in place of the standard air filter, it housed all the electrics - the battery, all the wires and the power supply unit, and the already manufactured air filter was placed on top of it.

in the end the motorcycle acquired its new look

To summarize, I’ll say that it turned out to be a good, good motorcycle, very high-torque (due to the ratio of the stars, the first gear turned out to be just a tractor), a spring from the UAZ clutch basket was added to the front fork in order to increase its rigidity a little - after all, the engine is noticeably heavier than the original one, and I weigh 103 kg … the suspension works just great! Well, the name of the motorcycle was given by crossing two “CZ and IZH” and the result was CHIZH (CHIZH)

See you on the roads, friends!

Motorcycles "Chezet"

It’s worth starting by getting to know the Chezet motorcycle as such. What kind of vehicle is this? In fact, everything is quite simple - these are motorcycles of Czechoslovak and then Czech production, which are called that only in Russia. “Chezet” is rather a nickname, because the original name is Česká zbrojovka Strakonice. Naturally, Russian people do not want to use such a name in their everyday speech, so he decided to simplify everything by shortening the name to indicate the country of production, that is, CZ. Well, then, if you pronounce these letters, then you get “Chezet”.

This plant has been operating since 1932 and initially concentrated on the production of mopeds. However, he quickly moved on to motorcycles, and in 1935 the first model appeared. Until 1998, the plant operated, producing a wide variety of motorcycles that became popular in Russia. Which Cheset motorcycle do you remember the most? Which was the first and which was the last?

Supply system

The standard "Yikov-2932" carburetor fully ensures normal engine operation in different modes if you use the main jet "135-140" and the idle jet "60-65".

The domestic K-194 carburetor also gives good results, but to install it you have to redo the pipe. To increase strength, it is advisable to cover the air purifier body with a layer of fiberglass with epoxy resin (ED-5, ED-6, K-153).

The muffler is located at the top.

Instead of a standard fuel tank, another, larger capacity (about 12 liters) is used, for example from a motorcycle IZH-11M or MTs-250.

Brief history of the model

1974 - start of production and sales. First generation
.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-A1.

1975 - no significant changes.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-A2.

1976 - no significant changes.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-A3.

1978 - no significant changes.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-A4.

1979 - no significant changes.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-A5.

1980 - no significant changes.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-A6.

1981 - no significant changes.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-A7.

1982 - restyling of the model. Second generation
.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-B1.

1983 - no significant changes.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-B2.

1984 - restyling of the model. Third generation
.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-C1.

1985 - restyling of the model. Fourth generation
.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-D1.

1986 - restyling of the model. Fifth generation
.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-E1.

1987 - no significant changes.

Model

: Kawasaki KX125 (North America).

Factory designation:

KX125-E2.

1988 - restyling of the model. Sixth generation
.

Model

: Kawasaki KX125 (North America, Europe, Japan).

Factory designation:

KX125-F1.

1989 - restyling of the model. Seventh generation
.

Model

: Kawasaki KX125 (North America, Europe, Japan).

Factory designation:

KX125-G1.

1990 - restyling of the model. Eighth generation
.

Model