tlrider Posted February 2, 2012 Report Share Posted February 2, 2012 Hi craig10, I believe it is a standard TL head, it has the same combustion chamber as a TL125S head I have. Currently it is at the shop, I'm having a larger exhaust valve from an XL125 fitted and a new TL intake valve fitted as well. THen to the platers to get ceramic coated to keep the heat down. I've read most if not all the info on kailas site, a wealth of info... I'm very interested in your fitting roller bearings. Is this in a one piece head? I have one that needs the journals repaired. My second big bore engine is to go in a Fraser MK2 frame for the TL, the one with the gas tank as the back bone. On that engine I'm putting a TL125S two piece head on a K bottom end; I need to work out the cam chain adjuster mod yet. I have done a basic layout but have stalled on the project. I picked up a TLR250 here in the States last summer and that is getting most of my attention. I'm looking forward to the pics of your cam bearing job. Scooter Quote Link to comment Share on other sites More sharing options...
craig10 Posted February 2, 2012 Report Share Posted February 2, 2012 It's a 2-piece head, originally I was going to use normal ball bearings 2 off 61807 47mm od at the cam chain end, but I ballsed it up and had to take it out to 48mm so I'm going to use a needle roller instead, but it needs a bit more work to keep the inner race in position on the camshaft. Doing it all on a lathe so not so easy to get the accuracy. Pete Arnold at PACRE just runs the cam direct in a needle roller at the small end on his race engines, 28od x 22id. The original idea came to me from a guy called Nigel Houlston who turned down the small end of the camshaft and made a hardened 'tyre' to run it in a needle roller of 28mm OD with the 61807 bearings at the cam chain end. I'm probably going to do a 47mm one as well, as originally planned, I bought some 'scrap ' heads off ebay to experiment with. Think it'd be a struggle with a one piece head without welding in an alloy ring to take the bearing at there's not much material thickness at that diameter. I actually did an outrigger bearing set up on a one-piece head which was total overkill. Someone else had done one just fitting a small ball bearing with shim round it behind the advance retard, if you're registered on Thumpertalk, http://www.thumpertalk.com/index , you will be able to see his pictures here http://www.thumpertalk.com/topic/724107-honda-single-cam-bearing-solution-why-not/page__fromsearch__1 Craig Quote Link to comment Share on other sites More sharing options...
tlrider Posted February 7, 2012 Report Share Posted February 7, 2012 Nicely done Craig. A much bigger job doing it all on a lathe. For the one piece head I've thought about putting in a large ring that will encompass the lobe cut outs and the original journal size. THe hole will be larger than the original journal. I would then make a bronze split ring that matches the cam journal with an appropriate od and flange to mate up to the new ring in the head. Haven't gone much past this thought, no sketches or measurments at this point just a thought. I'll have to register on Thumper Talk and check out the photos. I see the small end being a bigger problem on the one piece head due to the depth/diameter ratio more than the big end, an allusion on my part? Quote Link to comment Share on other sites More sharing options...
showtime45 Posted February 7, 2012 Report Share Posted February 7, 2012 While on the topic of TL125 cams, is there an easy way to distinguish between CL, CB, SL, & TL cams?? Seen some on Ebay but I'm not sure they are TL's. I Think some folks are trying to push a CB or such saying it's a TL cam trying to get more $$$$$$. Quote Link to comment Share on other sites More sharing options...
craig10 Posted February 12, 2012 Report Share Posted February 12, 2012 (edited) Nicely done Craig. A much bigger job doing it all on a lathe. For the one piece head I've thought about putting in a large ring that will encompass the lobe cut outs and the original journal size. THe hole will be larger than the original journal. I would then make a bronze split ring that matches the cam journal with an appropriate od and flange to mate up to the new ring in the head. Haven't gone much past this thought, no sketches or measurments at this point just a thought. I'll have to register on Thumper Talk and check out the photos. I see the small end being a bigger problem on the one piece head due to the depth/diameter ratio more than the big end, an allusion on my part? This was the jist of the thumpertalk thread, a shimmed bearing in the housing, drturnip's been running it for a year with just minor oil weepage The scrap heads I got were both worn out at the small end, the large end was actually acceptable on them. I've bored the small end to 28mm on the 2pc head I'm working on, it's a bit nerve wracking doing it on the lathe due to the overhang of the tool from the toolpost. I'll get a video up of it soon. Might not be too difficult on the 1pc head if you bore the chain side wall first to take your large support ring. It's an easier job to fit a bearing on the larger journal on a 2pc head as it's 34mm od with 32mm lobes so it can be bushed to 35 to take a bearing, if I remember right the 1pc head cam has a 30mm journal with 32mm lobes so not so easy without making a split bush as you say. Re the lad asking about the cams, the timings are different, not sure how you could tell the difference without putting them in a rig and timing them with a degree wheel. TL cams are like rocking horse doo-doo, I expect a lot of what's being offered are standard CB or XL cams. Some good info on Honda cams here http://vincentcrabtree.co.uk/XR200.aspx Edited February 12, 2012 by craig10 Quote Link to comment Share on other sites More sharing options...
rburk55 Posted December 5, 2013 Report Share Posted December 5, 2013 Was it ever confirmed that the 144 kit on ebay at he top of the post would work? Quote Link to comment Share on other sites More sharing options...
wfo speedracer Posted January 16, 2014 Report Share Posted January 16, 2014 I believe the general consensus is that i will fit 124cc engines but not 122's Quote Link to comment Share on other sites More sharing options...
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