Model 18: change of exhaust downpipe

blythmags · Post by **blythmags** » Sat Aug 11, 2012 10:06 am

Hi all..
In my quest to increase my exceptionally limited knowledge of motorcycle mechanics , I am going to attempt to replace a somewhat dreary looking exhaust downpipe on my 1950 Model 18 (when I eventually purchase same from Fecked.com).
I understand that this is the most basic of interventions, but is this process a straight forward loosening of the finned manifold clamp,taking the down pipe from the silencer and replacing exactly as is, without having to consider anything else along the way ?
Thanks in anticipation of your advice

dave16mct · Post by **dave16mct** » Sat Aug 11, 2012 10:40 am

Yes , you should have no problems. Give it a good squirt of WD now round the clamp, nust & bolts, and the join with the silencer and it should be easy when the new pipe comes. Use copperslip on the bolts when you re-assemble. Dave.

DWS · Post by **DWS** » Sat Aug 11, 2012 11:25 am

Just one word of advice, don't be tempted to knock the new pipe into the head with anything, even a plastic or hide hammer, it will dent your shiny new pipe! Don't ask me how I know

Rob Harknett · Post by **Rob Harknett** » Sat Aug 11, 2012 11:41 am

Just a word of warning. remove the silencer first, give it a clean while you have it off, if gunged up use cautic soda,seal the end with film and elastic bands leave overnight to do its work., Exhaust spigots are quite fragile. You may find the pipe stuck fast on the spigot. If so use penatrating oil, let that do the work not force. Twist, do not lever the pipe, keep it in line with the spigot. When off give the spiggot a good clean so the pipe fits easy, if theres no slits in the pipe cut 2/3 to a depth about half the length of the spigot. Assemble, loosely, fit the clamp loose, then pipe, use lubricant and twisting. If the spoggots clean the slits should open enough to get the pipe on, if not better cleaning of the spogot may be needed.. When fully home, fit the pipe bracket, this should hold the pipe fully home, now possition & tighten the clamp. Fit the silencer on the pipe to line up with its fixing point. The system should then stay put, not pop off. You may find you'll have to elongate the pipe bracket to allow the pipe to fit fully home on the spigot. thats why you sould make sure the pipes fitted first. Then it will stay held firm, the braket holding it so it can't pop off. The clamp really only to nip it tight on the spiggot. Its all basic stuff really.
But, be warned, dont use force getting the old pipe off and break the spiggot.Edited by - Rob Harknett on 11 Aug 2012 10:46:30 AM

blythmags · Post by **blythmags** » Sat Aug 11, 2012 11:45 am

Hi all
Many thanks for your excellent advice ( as always !)
Have a nice weekend....