mrshells Posted June 12, 2011 Report Share Posted June 12, 2011 I really need some help with my TY175 it started knocking a while ago so i had the top end off and fitted new little end gudgeon pin and piston rings, this made no difference what so ever !! So I sent it away for a rebore and crank build which was done with a NOS Hepolite piston with dykes rings as it should be and a new conrod and all the bearings when i got it back together it still knock as bad as before maybe a little worse !! can anyone give me a clue as to what to look for ? And please dont say they all do that cos they dont and this one never used to I was a a comp today with a guy whose TY was silent Quote Link to comment Share on other sites More sharing options...
charliechitlins Posted June 12, 2011 Report Share Posted June 12, 2011 There's knocking and there's knocking. Is it mechanical knocking, like a wristpin or crank? Detonation? Pre-ignition? All the time? Under load? When you're on the throttle? When you shut off? When you hit a bump? You get the idea... Quote Link to comment Share on other sites More sharing options...
mrshells Posted June 13, 2011 Author Report Share Posted June 13, 2011 Ok i get the idea it sounds mechanical hence the reason I had it Rebored and had the crank rebuilt at idle its there all the time but it does seem to go away when de-accelerating also above approx 25mph it appears to be not doing it it actually seems to get quiter the faster i ride it the annoying thing is its sound like wristpin or crank which is why i had it rebuilt but the noise is still the same and it runs great it just knocks I was asked yesterday if i was running on diesel ??? Im just trying to figure out how to start the engine after Ive taken off the clutch basket so i can eliminate crank and piston, I might start it with my windy ratchet later today Quote Link to comment Share on other sites More sharing options...
andy.t Posted June 13, 2011 Report Share Posted June 13, 2011 If the engine is running weak on low revs then it will knock like mad. You could try and check the pilot jet to see if its clear,could even need a bigger pilot jet.A leaking exhaust around the joint from the barrel doesn't help either. I had problems a little while back and fitted a 30 pilot jet, put a cooler plug in and problem solved. Quote Link to comment Share on other sites More sharing options...
mrshells Posted June 13, 2011 Author Report Share Posted June 13, 2011 (edited) Ill have a look at the carb in the morning Its not pinking its definatley a knock seriously it sounds like a diesel Im going to order an O ring kit anyway as none of them have ever been changed Edited June 13, 2011 by mrshells Quote Link to comment Share on other sites More sharing options...
andy.t Posted June 13, 2011 Report Share Posted June 13, 2011 Ill have a look at the carb in the morning Its not pinking its definatley a knock seriously it sounds like a diesel Im going to order an O ring kit anyway as none of them have ever been changed Yes this was a real knock on my bike and it was running very hot, was not the usual pinking noise, you will probably want to give the carb a real good clean theres a few air passage ways that connect with the pilot mixture.check the float bowl level and be sure the bowl is filling up to the correct level. just a thought when the bike is knocking try and give it some choke and see if it improves the noise, if it does then its running weak for whatever reason. Quote Link to comment Share on other sites More sharing options...
mrshells Posted June 13, 2011 Author Report Share Posted June 13, 2011 Yes this was a real knock on my bike and it was running very hot, was not the usual pinking noise, you will probably want to give the carb a real good clean theres a few air passage ways that connect with the pilot mixture.check the float bowl level and be sure the bowl is filling up to the correct level. just a thought when the bike is knocking try and give it some choke and see if it improves the noise, if it does then its running weak for whatever reason. thanks Andy Im going to give it a good looking at in the morning Im sure it will end up being something simple but its just annoying after have sourced a piston and having the crank re built it still knocks Ive had a listen with a screwdriver stuck in my earbut I cant even narrow it down other than is does sound like top end but is cant be as its all new !!! I can see it coming off tomorrow John Quote Link to comment Share on other sites More sharing options...
mrshells Posted June 14, 2011 Author Report Share Posted June 14, 2011 after extensive investigation the cranks F***** !! deflection a little end should be 0.8-1.0 mm ive got a whopping 3mm this is on a crank rebuilt by Grampians in Liverpool who have done many cranks for me in the past but not in the future !! its only had 10 hours at the most since rebuild Quote Link to comment Share on other sites More sharing options...
mrshells Posted June 14, 2011 Author Report Share Posted June 14, 2011 after extensive investigation the cranks F***** !! deflection a little end should be 0.8-1.0 mm ive got a whopping 3mm this is on a crank rebuilt by Grampians in Liverpool who have done many cranks for me in the past but not in the future !! its only had 10 hours at the most since rebuild having sat and read through the haynes manual on page 56 it has an exploded veiw of the crank parts 13 and 19 are shims and the manual states "as Required" but I can find no reference of a measurement that would tell me how thick the shims need to be Also looking on TYtrail UK website the parts list and diagram there does nor show or list shims ? so how does one set the endfloat on the crank when installing it ???? Quote Link to comment Share on other sites More sharing options...
charliechitlins Posted June 14, 2011 Report Share Posted June 14, 2011 Never done that particular bike but... You can put a dial indicator on the shaft and pull it in and out (same as you did to notice the endplay) and add shims, or you can put on too many shims and put the cases together. They'll rock because they won't close completely. Then remove shims one at a time until they stop rocking. That's zero endplay. Then remove the amount of shim equal to the recommended endplay. Quote Link to comment Share on other sites More sharing options...
andy.t Posted June 14, 2011 Report Share Posted June 14, 2011 (edited) not sure if this info is what you want but when the crank is pressed the measurement shown as D in the book should be 55.90 to 55.96 mm which should give you the correct float and the correct gap on the con rod, if its pressed too tight or too loose then that's where you end up getting problems. I am still amazed that's the problem as my old crank and con rod and little ends were well worn and had a worn piston with a broken ring and the engine really didn't sound bad at all. Edited June 14, 2011 by Andy.T Quote Link to comment Share on other sites More sharing options...
mrshells Posted June 14, 2011 Author Report Share Posted June 14, 2011 Never done that particular bike but... You can put a dial indicator on the shaft and pull it in and out (same as you did to notice the endplay) and add shims, or you can put on too many shims and put the cases together. They'll rock because they won't close completely. Then remove shims one at a time until they stop rocking. That's zero endplay. Then remove the amount of shim equal to the recommended endplay. Sorry Charlie the question was rhetorical My manual shows a shim on either side of the crank between the crank cheek and the bearing when installing the crank to clutch drive gear the retaining nut pulls the crank tight against the right side bearing so there is no physical movement of the crank to the left or right I have managed to find the part number for the shims but they are an obsolite part which itself is not a major problem as i can get sheet shim and make them I just dont know hwhat size to make them Quote Link to comment Share on other sites More sharing options...
mrshells Posted June 14, 2011 Author Report Share Posted June 14, 2011 not sure if this info is what you want but when the crank is pressed the measurement shown as D in the book should be 55.90 to 55.96 mm which should give you the correct float and the correct gap on the con rod, if its pressed too tight or too loose then that's where you end up getting problems. I am still amazed that's the problem as my old crank and con rod and little ends were well worn and had a worn piston with a broken ring and the engine really didn't sound bad at all. Ive seen some bads ones as well Andy Its gotta be done again its really bad and Im really P****d off not the cost, thats insignificant really its the fact it needs doing again Im the second owner of this bike Ive known it from new its only done 1100 miles in 35 years Im quite attached to it. but when i reinstate the crank its gotta be right I have the measurements thankyou but if the new rod kit with spacers is installed and the width of the crank pressed to 55.90 min tolerance and clearance between the rod and the crank web is still .5mm (more than max ) which is more important ? getting the end float on the big end right then everything gets pulled inwards from the points end of the crank effectivly making the crank to narrow for the cases the other question is whats the best rod to use ? Quote Link to comment Share on other sites More sharing options...
andy.t Posted June 15, 2011 Report Share Posted June 15, 2011 Ive seen some bads ones as well Andy Its gotta be done again its really bad and Im really P****d off not the cost, thats insignificant really its the fact it needs doing again Im the second owner of this bike Ive known it from new its only done 1100 miles in 35 years Im quite attached to it. but when i reinstate the crank its gotta be right I have the measurements thankyou but if the new rod kit with spacers is installed and the width of the crank pressed to 55.90 min tolerance and clearance between the rod and the crank web is still .5mm (more than max ) which is more important ? getting the end float on the big end right then everything gets pulled inwards from the points end of the crank effectivly making the crank to narrow for the cases the other question is whats the best rod to use ? Not sure of the best one to use but mine was fitted with a LONG(trade name) connecting rod kit made in JAPAN..stock no CK4152...YAMAHA DT175E/F/G...(2N4-11651-00) , My local Yamaha dealer got it in for me and then had a company press it for me. I did have to get them to re press it as it was too tight when they gave it back to me. Good luck Quote Link to comment Share on other sites More sharing options...
subanator Posted June 15, 2011 Report Share Posted June 15, 2011 (edited) See HEREand download either section 3 PDF that relates to the engine, or the rest also for ref. Page 93 is what you want to know. I saved off the Yamaha Sport the parts list, this item is the shims as: 132-11561-00-03 SHIM, CRANK (25.5-35-0.3) U. R. 132-11561-00-05 SHIM, CRANK (25.5-35-0.5) 1 136-11561-00-03 SHIM, CRANK (20-30-0.3) 136-11561-00-04 SHIM, CRANK (20-30-0.4) U. R. 136-11561-00-05 SHIM, CRANK (20-30-0.5) 136-11561-00-06 SHIM, CRANK (20-30-0.6) 136-11561-00-07 SHIM, CRANK (20-30-0.7) These part numbers may differ per country, as these are for Nth America Edited June 15, 2011 by subanator Quote Link to comment Share on other sites More sharing options...
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