This Invention relates to a telescopic front fork of a motorcycle, which is rendered noise free during operation.
In the conventional telescopic front forks of motorcycles known to the art, the spindle taper Is used for generating high damping force in the full bump condition to avoid the metal-to-metal contact at the bottom. However, this system produces noise at the beginning of the extension stroke due to creation of vacuum in the compression chamber. This phenomenon is prominent when the stroke of the fork is more, when the inner tube crosses over the compression damping holes and reaches spindle taper. The inner tube has a component called piece oil lock which slides over the spindle taper during stroking. ThApiece oil lock A_spindle taper are two Darts_ which_ perform the basic .^ function of qeneratinp high oil lo^k force by increasinqly reducing, the area.ayailqble for_oil to flow^,towards_ the end of the stroke. The pjece oil lock Is basically, g cylindrical Dart normally .fixed inside the inner tube & ixs jmer dlame-fer has small clearance with the outer djameter ^f_the spindle taper. Piece oil lock also suDDorts the damping control valve on the topside. Towards the end of Stroke the piece oil lock moves overijhe jSDljndle taper A reduces the oil flow passage. This

squeezes the oil through a narrow passage thereby increasing the clamping reslsiance and resulting m nn increased force called oil lock force.
The above limitation Is overcome by the provision of a checkvalve (also referred to as a one-way valve). The required function is achieved by having a suitable locking of the checkvalve on the spindle taper by providing a groove on the spindle taper. A feature,_ like a _step n:^-^ •: r^-'a^ir' on the check valve fits into the groove m the spindle taper with suitable interference fit so as to avoid any oil flow through it and also holds the checkvalve \r\ place during the stroking cycles. The checkvalve has an extension at the bottom in the form of a cylinder, which covers the holes on the spindle taper thereby closing the oil flow path through the spindle taper. The check valve is made of flexible material like rubber (different materials can constitute different embodiments) During start of extension stroke, just as the vacuum starts to form, the cylindrical portion of the checkvalve expands under the extension suction force. This enables partial opening of the checkvalve thus creating a circumferential passage for the flow to oil. Oil flows through this passage

and the vacuum formation Is avoided, thereby eliminating occurrence of any noise phenomenon.
This invention will now be described with reference to the accompanying drawings, which Illustrate by way of example, and not by way of limitation, one of its possible embodiments wherein
Fig. 1 illustrates the assembly of the front
fork
Fig. 2 illustrates a view in detail of what Is
shown in Fig.l
Fig. 3 Illustrates the piston
Fig.4 illustrates the check-valve
•H^f ig.5 illustrates spindle taper
And fig 6 illustrates piece oil lock
When the compression stroke takes place, once the inner tube I passes the compression damping

holes H, there will be high pressure in the compression chamber C as there Is very restricted path for oil to flow from the clearance of inner tube inner diameter of the piece oil lock P and spindle taper 5 outer diameter. This is intentionally maintained to develop adequate oil locking force. The checkvalve V will be kept compressed on the holes H on account of fluid pressure thus closing the holes on the spindle taper T in compression stroke. C. Alternatively the checj<_yalye V will be kept under preload thus closing ,the_ holeSt__pjn the spindle taper T in compression stroke._C
In the conventional fork, at the end of compression stroke, the inner tube I will start to move back creating more volume in the compression chamber C but oil supply being very restricted; it will start creating vacuum. As this happens in a very small interval of time, a vacuum noise gets created. To avoid the noise from occurring it is necessary to have some means of providing adequate oil supply at that moment.
This IS Qch'iewed by providing a flow path F for oil from inside the second chamber S to the chamber C as shown by the arrows A. The flow of oil takes place due to the pressure differential on

both sides of the checkvalve, resulting \r\ expansion of the check valve, providing oil flow path F through holes H for oil to flow into the compression chamber C during the extension stroke.
Thus by avoiding the vacuum m the compression chamber and ensuring adequate oil supply at the right time through creation of path way for oil flow, the noise can be eliminated.
The invention proposed herein has advantages m that it Is simple and requires little modification in the existing telescopic fork design, Is cost-effective & has m slid]]iq_ 5arts_thus avold^lnq additional Sjourcejof noise, Additionally the check-valve Is firmly located m place with the help of a groove, such as, a rectangular groove on the spindle taper. The part of the ched